To debit a transaction from the E-Pay Transactions page:
Hover over the last column in the appropriate row and click the Preview button.
In the details form, click REVERSE.
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Click YES in the confirmation message. The Issue Credit dialog is displayed.
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The amount field is populated with the original amount from the transaction that is being reversed.
The amount field can be changed but cannot exceed the previous amount of the transaction being reversed.
Submitting the credit calls the gateway to issue a credit against the original transaction ID.
If the credit against the original transaction fails the system calls the gateway and attempts to issue a blind credit.