A Partial Approval transaction can be voided using the Void transaction. However, you must process a separate void for each partially approved transaction that makes up the total transaction amount. Use the printed merchant receipts to identify the individual transactions if needed. The transaction to be voided must be in the current batch on your terminal. If cash was used to pay for the remaining balance of the total purchase, then perform a cash refund for that amount since you cannot void a cash transaction.
For example, if a partial approval transaction was processed for a total of $57.75 using two pre-paid cards, one for $20 and another for $30, with the remaining balance of $7.75 paid as cash, you would need to perform two separate voids and one refund:
§ a debit/credit void for $20;
§ another debit/credit void for $30; and
§ a cash refund transaction for $7.75, since you cannot void a cash transaction.
General guidelines for performing transactions