A registration can change after you first create it. A registrant might add a session, drop a function ticket, or cancel entirely, and the order for that change must reach the registration before you see the update there. Rhythm applies paid modifications and cancellations automatically after Commerce reports the matching order as paid or cancelled, so you do not need to update the registration by hand.
Modifications
When a registrant pays to change an existing registration, Rhythm updates the original registration after the change order is paid. This includes adding a session, function ticket, or another paid item. Rhythm matches the registrant's other event purchases by contact and event, not only by order, so a change can also affect items bought on another order for the same person at the same event.
One exception protects tickets the registrant bought before a function sold out. If a function is currently marked sold out, a modification does not replace a ticket the registrant already holds for that function. The registrant keeps the ticket even though the function shows no capacity, and if the same modification adds another ticket to that function, the registrant ends up with both tickets. Sold-out functions and sessions can block a modification in other cases. If the change would add or keep a sold-out item outside that protected case, the edit can fail. A scheduling conflict that the form will not let you clear can block a modification the same way. If a completed registration already has that kind of conflict, treat it as inconsistent data rather than something you did wrong.
Modify Order only adds to a registration; it is not the tool for taking anything away. It can add a session, function ticket, guest, course, or add-on, but it cannot cancel or reduce a session, function ticket, or add-on that is already on the registration. It also does not let a registrant switch to a different registration package. A person can hold only one registration package at a time, and Modify Order does not change that package while it adds sessions, functions, and add-ons on top of it. If a previously cancelled session still shows as selected the next time you open Modify Order, removal is not handled through modification, so cancel the item instead as described later in this article. The same is true for function tickets. Modify Order can add more tickets, but it cannot reduce an existing ticket quantity to zero, and the validation requiring at least 1 reflects that limit. To remove a previously selected function, or to move someone to a different package, cancel the existing registration and process a new one instead. Once a registration is submitted, its package cannot be changed by editing the order or by impersonating the registrant. Because modification never removes anything, it also never creates a refund. If the change should send money back to the registrant, handle it as a cancellation instead.
Removing an item through a modification, in the Portal or the console, does not make Rhythm recalculate the order's pricing or line items. The order stays as it was originally created, even though the registration record shows the change. The reverse is also true: editing an invoice directly does not update the related registration order. Use the registration's own modification flow, not a direct invoice edit, whenever a registration's pricing needs to change. If you edit a registration's package by hand outside that flow, Rhythm does not add the cost difference to the existing invoice or order automatically, so you need a separate invoice to collect it.
Whether Modify Order is available depends on configuration, not just on what the registrant wants to do. The registration's process must allow modifications, and a change fee must be set up for anything that should be charged. If you turn off registrant edits to stop Portal users from editing their own registrations, staff lose this path too because the same setting controls both.
A coupon code cannot be removed from an existing registration order after it has been applied. If a coupon was used by mistake, cancel the order and reprocess the registration without it instead of trying to edit out the coupon. This also matters during a modification. When a change fee comes to $0.00, the modification flow does not offer a way to remove a coupon that is already on the order, so a coupon carried over from the original registration cannot be cleared there either.
When a registration's process does not allow modifications, or Modify Order is not otherwise available, staff still have manual ways to add to a registration. Use Edit Manually on Registration 360 to add sessions, function tickets, or a guest registration directly. Use Orders & Inventory for something Modify Order cannot handle, such as exchanging one function ticket for another. These manual paths do not charge the registrant automatically the way Modify Order does, so you need a separate invoice to collect any fee. The Orders & Inventory workaround can lose linked details, such as a function ticket's meal choice or other answers, so treat it as a fallback rather than a routine substitute. From an attendee's Registration 360 record, staff can also start Modify Order the same way a registrant would, to add a session or function ticket for the registrant.
Within a group registration, changing one attendee to a lower-priced package or type through a modification can post a credit for the difference to the paying account instead of creating a new invoice for just the difference. If a group modification does not behave the way you expect, check the account for a credit.
After Rhythm applies a modification, it sends the registrant a new confirmation that summarizes the registration as it now stands. Rhythm uses the confirmation process that resolves and has confirmation enabled. For a group registration, this confirmation always goes to the registrant; the group-administrator recipient choices from the original registration confirmation do not apply again. Registration 360 also shows exactly when a registration was created and when it was last modified, in a Last Modification Date field, so you can confirm the change took effect without waiting for the confirmation email.
Tip
Adding sessions, functions, courses, or add-ons through Modify Order from the registration does not change the original order's totals. Rhythm creates the added items on a separate order, with its own invoice among the contact's open invoices. Registration 360 shows the added items on the registration, but the original order total stays the same. If you need the combined total, check the contact's invoices instead of the original order.
The invoice for a paid modification shows only the change-fee product's own name as its line-item description. It does not show the more detailed text you would see on the order, so it will not spell out which registrant, package, or change the fee covers. Rhythm also posts a change-fee entry to the general ledger for the change, and that entry may or may not carry a dollar amount depending on what was charged. If you are reviewing a change order alongside the original registration, note that change fees are listed before the registration in that view.
Adding a function ticket directly from the registration works differently when you use the add-ticket action instead of modifying the order. That action issues the ticket to the registrant, but it does not change any invoice amount because it bypasses the normal order-change process. If the invoice needs to include a ticket added this way, plan to handle that separately.
Reporting on a Modified Registration
Because a modification's items live on a separate order, a registration query can undercount what a registrant holds and paid. The registration query's own Order Amount Paid field reflects only the original order, not any later change order, so it never adds the two together. An open-balance query for event registrations works the same way: it shows only the original order's balance due, not charges added through a later modification. A registration's Amount Paid and Balance Due can look complete while a later function ticket or session bought through a change order shows no payment information, especially when that later item was paid on its own separate order. Treat a blank or zero payment field on a later add-on as a reason to check the contact's invoices, not as proof that nothing was paid. The registration query also will not show a flag or an extra row telling you a registration has a related change order. A modified registration's original-order fields look the same as if it had never changed. A change-fee order is a separate financial record from the original registration order for the same reason, so do not assume it can stand in as a registration's main linked order when you are looking up or linking orders for someone.
To see a modification's charges, look outside the original registration query. An Orders query filtered to the event returns every order tied to that event, including orders created by modifications. That makes it a more reliable way to total what a registrant paid across their original and modified orders than the registration's own fields. The same applies to a coupon or discount used on a registration. Pull it from the Orders output fields, such as Coupon Code ID(s) (Orders) or Discounts (Orders), rather than the similarly named fields under Registration, which may not carry it. For a group registration, remember that an event query shows only the original registrations. Anything purchased afterward through a modification is a separate order with its own order date, and you need an order query to see it.
Registration 360 shows the same split. It displays sessions, functions, add-ons, and other items added through a later Modify Order, but if you add an unpaid add-on and choose to invoice or pay later, the open balance shown on Registration 360 can still reflect only the original registration. The newer amount due is visible only in Orders. The registration query's Amount Paid field for a guest registration does correctly return that guest's own amount paid.
Cancellations
Cancelling the order behind a registration package is what cancels the registration. When Commerce reports that a registration package order line has been cancelled or refunded, Rhythm cancels the matching registration no matter what status it currently has, including draft. This is the confirmed rule whether the cancellation starts from the order or from the registration itself; either path should leave the registration cancelled.
Warning
This rule depends on cancelling the package order line itself, not only its payment. If you handle the cancellation only at the payment level, such as cancelling or refunding a payment record without cancelling the order line it paid for, the registration can still show active even though the money was refunded. If you need the registration to show cancelled, cancel it on the order instead of working only with its payments. If the cancellation was already handled incompletely this way, you may need to cancel the outstanding payment and then change the registration's status by hand.
The same manual correction covers a few related situations: an order that has already been refunded but whose registration is still active; a cancelled and refunded substitute registrant who still appears on an active-registrant list; and any registration a saved query flags as belonging to a cancelled order. For an active registration tied to an already refunded order, edit the registration and set its status to Cancelled directly, using Edit Manually rather than repeating the cancellation action. Building a query to catch cancelled orders whose registrations are still active is a useful way to find these before a registrant notices. When several registrations need the same fix, use Event Registration search to find them and a query mass update to set their status to Cancelled together, rather than fixing one at a time. If the normal cancellation path is blocked because the order's invoice was already voided, manually set the registration to Cancelled and then close the order, since neither will resolve on its own.
Because only the order-level cancellation reliably updates the registration, do not try to move a registration to a different card, or otherwise fix a payment problem, by working directly in payment tools. Reverse the original registration and payment the normal way and create a new registration payment instead.
If a registration is missing the order link entirely on its Registration 360 record, rather than just showing the wrong status, Support can fix that separate problem by relinking the order. Relinking does not necessarily restore a guest registration that was part of the original purchase. If a guest is missing after a relink, add the guest back through the registration's own modification flow and override the guest registration price to $0 so the registrant is not charged again.
Cancelling a registrant's order line cancels more than the registrant's own registration:
- Guests and their courses. Rhythm cancels every guest registration linked to the cancelled registration, along with any course registration a guest was enrolled in through the event.
- Certification credits. Rhythm removes any certification credits the registration earned when the registration is cancelled.
- The webinar join link. If Commerce's cancellation runs, rather than a direct edit to the registration's status, Rhythm removes the cancelled registrant from the event's Zoom webinar or meeting, so their join link stops working. Editing the registration status directly does not remove the registrant from the webinar this way.
A registration's package order line is specifically what has to be cancelled for the registration to follow. Cancelling a different order tied to the same registrant does not cancel the registration. For example, if a backend order was invoiced using merchandise items instead of the event registration fee product, cancelling that order will not cancel the attendee's registration at all. You need to cancel the registration separately, then create a new order and registration for the replacement event.
Cancelling a registration does not send the registrant a cancellation email. If the registrant needs confirmation that the cancellation went through, you need to tell them yourself. A cancellation does free capacity for the event's waitlist. Whether you cancel a whole order through the Portal or cancel just one line item in the console, the released spot becomes available to the next eligible person on the waitlist.
Applying a full credit memo to a registration's invoice changes the invoice's own status to Cancelled, but it does not necessarily close the related registration order, even after the balance due reaches $0.00. Check the order itself, not just the invoice, before you assume the cancellation is complete. A cancelled registration order's own invoice does correctly show Cancelled, both on the invoice record and in invoice queries. If you refund a registration or function ticket directly from the payment screen instead of cancelling the order item, the order item stays active and the order keeps showing an open balance because Rhythm still expects payment for it. Cancel the registration item from the order screen instead, and choose the option to skip the electronic refund so Rhythm records a credit memo to offset the balance rather than trying to refund money that was already returned another way. Once a credit, coupon, or cancellation adjustment brings an order's balance to $0.00, close the order to show it as completed while leaving the registration itself active.
If a paid registration order has already been deleted, you cannot reinstate the original record, even though the payment itself may still show correctly in your payment processor's settlement records. Recreate the registration order and record the original payment on it manually so finance can reconcile it against the original transaction.
Guest Registrations and Cancellations
Cancelling only a guest's own registration, rather than the whole party, should set that guest's registration to Cancelled while leaving the parent registrant and a paid order untouched. In some cases, the guest registration may keep showing Active longer than expected, or the related order may reopen to Open even though it was already paid. If that happens, treat it like any other incomplete cancellation and correct the guest's status directly.
A cancelled guest registration can also behave inconsistently in a few other ways worth checking. The guest may still appear on Registration 360's Guests tab as active, even though the guest's own record shows Cancelled. In that case, the tab display and the record itself disagree. Removing a guest during a registration modification, or cancelling the guest registration from the order, does not always clear the guest from the primary registrant's own registration record. The guest can still show as linked after you have cancelled or removed them. If a guest who has, or became, a contact record was cancelled or removed this way, they can still be treated as already registered if they later try to register for the event on their own. Cancelling the guest registration does not always fully clear that state. If you see a guest registration duplicated on the record, in queries, or in reports, modifying the order, cancelling, refunding, re-registering, or merging the underlying contact records do not reliably clear the duplicate. Contact Support rather than trying each of those in turn.
A correction made to how guest cancellations are handled applies only going forward, to orders processed after the fix, not retroactively. If a guest registration from before that point still shows the wrong status, correct it by hand the same way you would any other registration whose status did not update from its order.
Cancellation Fees
A cancellation fee needs two things configured before Rhythm can charge one, not just a fee amount. An administrator first creates a cancellation fee product under Finance & Billing's miscellaneous products, then selects that product as the event's Cancellation Fee Product in Registration Settings. The amount charged comes from the fee set on the registration package itself, and that package-level amount overrides whatever amount is set on the miscellaneous product. Configuring the miscellaneous product alone does not charge anyone a fee. The registration package also has to be set up to charge one, or nothing happens at cancellation even though the product exists.
When a registration is cancelled without waiving the fee, Rhythm generates a cancellation fee invoice and pays it from the store credit created by the cancellation, then refunds any amount left over to the original payment method. In most cases, that credit applies to the fee invoice automatically, though you may need to apply it yourself if it is left sitting unapplied. Cancelling an order with more than one cancellation fee should create matching offsetting transactions and charge each configured fee amount. In some cases, a cancellation fee invoice can remain as an open invoice balance even when the rest of the registration was cancelled without a charge, such as when a coupon reduced it to $0.00. That outstanding fee balance is separate from whatever happened to the rest of the order. Occasionally, a cancellation fee can be overstated and leave an incorrect balance due after the cancellation, or a cancellation on an order with two or more cancellation-fee items can fail to complete. If either happens, treat it as a cancellation that needs Support's help rather than trying to force it through again. If an automated cancellation does not go through at all, you can manually set the registration to Cancelled and collect the cancellation fee separately with a one-off store order using the cancellation fee product. A correction to how registrations paid with store credit are handled applies across every event, not only the one where it was first noticed.
If you need to charge a cancellation fee that is different from the amount Rhythm applies automatically, remember that Rhythm does not let you edit the dollar amount on an existing order. Cancel or credit the order that has the wrong fee and create a corrected one instead of trying to adjust the balance in place.
Cancelling One Item Without Cancelling Everything
From the order, selecting Cancel Order opens a modal that lists the registration's items, with a Qty to Cancel column and an option to waive any fee. Set an item's quantity to 1 to include it in the cancellation, or leave it at 0 to keep it on the registration. This is how you cancel just a session, function ticket, or add-on without touching the rest. To cancel one add-on or fee line while leaving the registration package in place, set the package line's quantity to 0 and the specific item's quantity to 1. The reverse combination cancels the whole registration instead. Which registrations get cancelled from a partial or group cancellation depends entirely on which rows are marked in this grid. A registration that is not selected stays Completed even if you expected the cancellation to reach it, so check the selection carefully, especially on a group order where guest and primary-attendee rows are listed separately. After a partial cancellation on a group order, cancelling any additional remaining items on that same order can fail. There is no workaround for this yet, so if you hit it, contact Support rather than repeating the attempt.
Not every cancelled order line cancels the whole registration. Some lines cancel only the item they paid for and leave the rest of the registration in place:
- A session fee line cancels the matching session registration. If Rhythm cannot match the fee to a specific session registration, it may cancel a different session registration for the same contact at the same event instead of leaving all of them active.
- A function fee line cancels the right number of function tickets for that fee. If no tickets qualify to be cancelled, Rhythm does not cancel anything, and the mismatch is only logged instead of shown to anyone. Staff can also cancel a single function ticket directly, without cancelling the whole registration, by opening the order and refunding or cancelling that ticket's line item. To remove a function ticket from a registration entirely, cancel the registration order line item using
Cancel Registration Orderand reprocess the order without that ticket. - An add-on order line removes that add-on from the registration that holds it. If more than one registration for the contact holds the same add-on, Rhythm changes only the first one it finds. Removing an add-on this way is separate from whether the registrant was actually charged for it, so check the invoice and balance due. An item can come off the registration without automatically reversing a charge already made.
Cancellation fees for add-ons such as guest registrations, course registrations, and function tickets apply only when you cancel the item this way, not when you remove it during a modification.
Modify Order is for adding to a registration, not for taking anything away, so removing a session is a cancellation, not a modification. A registrant can cancel only their whole order from the Portal; cancelling just one session is a console task. Open the registration and use Cancel Order to cancel, and if appropriate refund, that one session, using Cancel Registration Order rather than Modify Order. Choosing the option to skip the electronic refund records a credit memo instead, which is useful if the payment was already returned another way. To handle everyone affected by cancelling a single session at once, run a Sessions › Session Registrations query filtered to that session, then work through each affected registrant's Registration 360 the same way, cancelling just that session's line. If a session is over capacity rather than genuinely cancelled, adding a session cancellation date to the session registration removes the attendee from the session. If the event also feeds an external learning platform, confirm the removal reached it, since you may need to remove the person there separately.
Session registrations are identified against a specific registration instance, not just against the session and contact. Because of that, cancelling a session on one registration and later creating a brand-new registration for the same person and session should create a fresh, active session registration rather than reusing the cancelled one. In some cases, you may still see the person listed under the earlier cancelled entry. If that happens, treat it as a data mismatch to correct, not as proof the person is unregistered. If a cancelled registration's sessions are not cleared when the registration itself is cancelled, they can still show as selected the next time someone opens the Portal's modify-registration flow on a new registration for that same contact and event, blocking sessions in the same time slot. Check the earlier cancelled registration if that happens. Voiding an order for a paid session can also leave a session-registration relationship in place that blocks deleting the session afterward, even when the equivalent no-fee, manually created registration can be deleted without issue.
A change to an existing registration can create later orders that are separate from the original one, so cancelling a session by changing its status directly on the session does not cancel the order behind it. You still need to cancel the later order created by that change. Otherwise, the session can keep appearing in purchase history and in anything fed by an integration, even after its status looks cancelled. If an integration's session list does not match what you expect, check purchase history for an order that still needs to be cancelled before assuming the integration failed to update.
If a registration processed with Invoice Me/Pay Later is later cancelled or reduced, its function ticket status can occasionally stay Active instead of following the registration. Check the ticket status directly if that happens. If refunding one of several function tickets on the same order appears to update the wrong ticket's status, correct the affected ticket's status by hand rather than assuming your own action was wrong. Similarly, if you find a case where a registrant was billed once but a function shows the person registered twice, that is a sign of a known duplication defect, not something to fix on the registration itself. If duplicate function registrations have built up for the same person more broadly, work through them by comparing the registrations and their related change orders or modifications one by one. Then consolidate them back into a single registration or order so your totals are not counted twice.
If you are deciding between modifying and cancelling a registration, use cancellation whenever the change should produce a refund. Modification never refunds money; only cancellation does.
Why a Cancelled Item Can Disappear from Reports
Cancelling an order line removes that item from the attendee's record. That means a query or report that once counted a session or add-on for a contact can stop counting it after the order line is cancelled, even though the contact paid for it at one point. If an event query number looks lower than you expect for something a contact previously bought, check whether the order line behind it was later cancelled. When add-on participation does not match between a report and what a person actually holds, the attendee's own registration list and individual registration record are usually more reliable than an order-based report, especially when the underlying order data is incomplete. Compare the two views to see what is missing.
Cancellation Takes a Moment
Cancelling an order does not update every linked record instantly. Rhythm processes the cancellation automatically shortly afterward, so a registration or guest registration can still show its earlier status for a brief period after you cancel the order. If the status still has not changed after you give it a little time, check the order to confirm the cancellation went through before you assume something else is wrong.
This delay can affect reporting too. An event's Active Registrations counts and KPI tiles may lag behind a completed registration or cancellation by anywhere from a few minutes to noticeably longer in rare cases, so do not treat a briefly wrong count as proof the cancellation or registration failed. Cancelling one person out of a group order can also take longer than usual to reach that person's own registration status. If a cancelled order still shows an active registration after you have allowed reasonable time for it to catch up, report it within about a week of the order date, while the activity is still easy to investigate. A cancelled or voided group registration can also fail to show as cancelled at the contact level even after the registration record itself is correct, so check the registration directly rather than relying only on the contact's summary.
Correcting a Mistaken Amount
Rhythm does not let you edit the dollar amount on an order after it has been created. If a price on an existing order is wrong, cancel that order, or the affected line, and create a corrected one instead of editing the original amount.
This is the pattern behind several common pricing corrections. To move a registration from a non-member rate to a member rate, cancel the registration order that used the non-member rate and process a new registration order at the member rate. To reflect a changed registration package in your financial records, cancel the existing registration order and create a new one so the order and invoice match the updated package. If the wrong package was used and it cannot be changed through a modification, the same pattern applies: cancel the existing registration and order, issue store credit during that cancellation, and create a new registration with the correct package, applying the available credit. Cancelling a registration order this way returns the original payment as a refund or as store credit for future purchases, and either can then be applied toward a corrected order at the right rate.
For a registration placed under the wrong package entirely, a clean fix is to cancel the original registration's package line, issue store credit for the amount already paid, create the new registration under the correct package as an open invoice, apply the store credit to that invoice, and send the registrant a payment link for anything still owed. This keeps reporting and package allocation correct going forward.
A group registration with a coupon misapplied before payment has two recovery paths, and neither removes the coupon from an order it is already on. You can change the affected registrants back to Draft so they return to Pending Registration and can be purchased again through Complete Group Purchase as a separate order and invoice. Or, you can cancel the whole order and reprocess the group registration so pricing is corrected during a fresh purchase.
If a registrant was priced using a group discount they should have received, but the registration is corrected by hand after the fact, Rhythm does not automatically reconcile the missed discount. Issue a manual refund or credit for the difference instead.
A registration's own balance due does not always refresh automatically after a refund or an invoice adjustment. Try resaving the order first. If that does not update the registration's balance, correct it directly from Registration 360's Edit Manually screen, using the Order Related Information link to bring the balance due back to zero. Audit logs can show who last changed a registration's order-related values if you need to track down how a leftover balance got there.
Registration Changes and the API
If you are integrating with registrations, use the registration record's sys_last_modified_at field to detect what has changed instead of polling every record. It updates when a pending order is paid and the registration completes, when the registration form is edited, and when tickets are added or adjusted. The single registration lookup endpoint only returns one registration by its own ID and does not accept the criteria-based parameters a change-detection integration needs. To find every registration modified since your last sync, run a query-style request filtered on sys_last_modified_at instead. There is no caching layer in front of these registration updates, so a function added or removed through a modification is available through the normal endpoint response as soon as the registration itself is updated, with no extra delay to plan around.
Example
A registrant who already has a paid registration adds a workshop session through Modify Order. Because the workshop's function has sold out its meal option, the workshop's own function fee still goes on a separate order, and the registrant's original invoice is untouched. The new session appears on the registration after that separate order is paid.
Later, the registrant cancels the whole registration from the order. Rhythm cancels the registration, cancels the registrant's one guest registration, removes the certification credits the registration had earned, and removes the registrant's Zoom join link because the cancellation ran through Commerce. Rhythm also cancels the workshop session added earlier because it matched the same contact and event, even though it came from a different order than the one just cancelled. Because both the session and the registration package are now cancelled, the places they held become available to the next eligible person on the event's waitlist.