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When a Refund is performed, the sale system or the device control (eg. the MerchantApp) may provide Refund Reference Data as a reference to the original Service being refunded.
Refund Reference Data may be identical to the Reference Data of the original Service, but this is not mandatory and not checked.
Refund Reference Data is not used to retrieve the transaction data of the original Service, but it is stored in the transaction database for the Refund.
Refund Reference Data (optional) : DF59
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