You can refund or cancel a transactions previously performed on the payment terminal.
To proceed with a refund or cancellation, go to:
Select Menu > Receipts > Select the transaction
Cancellation
A cancellation should be done within same day after accepting the payment and on the same terminal used for the original transaction. Card of the cardholder is not required for a cancellation. It can only be done associated to a previous transaction.
Refund
A refund can be done at any time and require a card to be effective. It does not have to be associated to a previous transaction.
These operations are protected by a 4 digits password, if you don’t know it contact customer support.