Merchant code hopping.

POS code hopping refers to merchant code hopping, which refers to the Merchant Category Code (MCC) on the purchase form and the UnionPay official back-end Merchant Category Code (MCC) data when the cardholder swipes the card at the POS machine. Inconsistency means that the original merchant is displayed on your receipt, but the merchant with the skipped code is displayed in the UnionPay backend. The POS machine reads the cardholder's magnetic stripe information on the bank card through a card reader. The POS operator enters the transaction amount, and the cardholder enters personal identification information (ie, password). The POS sends this information to the UnionPay center. The card-issuing bank system completes the online transaction, gives information on success or failure, and prints the corresponding receipt.