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For each swipe, Samsung sends over a different credit card number for encryption purposes. So, therefore, the pre-auth amount is charged at each swipe. When the amount is settled, the customer is only charged for what they spent at the machine. *NOTE* This will be fixed in the August 2019 FasCard Firmware Core 8.00 Release.
What is a Digital Card Number and how is it different from my Card Account Number?
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