This happens when you are refunding via credit card with no P/N Ref. number available on Transactions > Customers > Issue Customer Refund > Refund Method tab > Process Credit Card checked.
The processor is trying to identify a P/N Ref. that was previously processed/charged on the card. In order to refund on the card, the credit card merchant attempts to look for the P/N Ref. that was generated on the payment record.
To solve the issue, process with the following steps:
- Navigate to the Invoice that you intend to process the refund for and look for the payment under Related Record tab.
- Open the payment record and look under Payment Method tab for the P/N Ref.
- Copy the number.
- Go back to Transactions > Customers > Issue Customer Refund > Refund Method tab > paste the P/N Ref. number.
- Process the refund and it will go through.
Note: There are some gateways that allow refunds and credits even without an actual credit card charge. Refer to your Credit Card Gateway for assistance.