in the case of China merchants bank credit card, cvv2 is the verification code, which generally refers to the last three digits of the signature column on the back of your credit card. For example: 1234 567, just enter 567. The verification code will change every time you change your credit card. If it is blurred, you can cover it here with white paper and draw it repeatedly to show these three digits. If the input error is locked for many times, it will be restored every other day. This verification code can only be viewed by the customer's own card.

one is the card information, which includes the 16-digit card number, expiration date and the last three verification codes on the back of the card. These information must not be disclosed. The last three digits located at the signature on the back of a credit card, also known as CVV code or CVC code, are generated by the coding rules and encryption algorithm of the issuing bank. Generally speaking, these three numbers are unique and used to identify individuals. In the process of payment, especially off-site payment, if the merchant provides the "last three digits" to the bank, the bank will allow the transaction by default for the merchant to obtain the authorization of the cardholder.

cardholders should pay attention to the card environment when using their cards, and don't log in to mobile banking and online banking in public internet cafes or cafes, so as to avoid being stolen in an unsafe network environment when entering the verification code, mobile phone number and other information. Once you find a stolen brush, call the bank as soon as possible, make a loss report, and then call the police.