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If there are credit card installments attached to an invoice, you first need to unlink the credit card from the invoice, then you can make the exchange (see below for instructions)
if a refund was made on an invoice, unfortunately, you will not be able to make an exchange. If it was a partial refund, an option you can use is to cancel the registration, but don’t refund the remaining amount. Then add a new registration, and adjust the amount to the outstanding balance.
Exchange a Package with Installments
When a registration is set up with installments, and the method of payment is credit card, the Exchange Items will be grayed out, you must first unlink installment from the credit card then you can do the exchange of an item
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