[S-Pay] Why it does not work after I give the last 4 digit of my card to the cashier?

In rare cases, the merchant may ask the you for the last four digits of the card number.

You will need to provide the last four digits of the digital card number, instead of the last four digits of the physcial card. For ease of use, it is located on the left side of the card in the Simple Pay screen, and in the main app when viewing your registered cards.