If you cancel a participant’s registration and they paid by installments using a credit card, you will need to edit the transactions and change the method of payment to an offline option.
Go to the member's profile
Click on the Transaction tab
Click on the transaction for which you wish to cancel payments, a side panel will open on the right
Click on Edit in the registration box next to the member's name.
Change future payment methods by selecting one of these choices Cheque, Cash, or Manual Interac E-transfer, External Payment or Offline Credit, then click Confirm.