1. The credit card is damaged or degaussed: The credit card has been used for a long time or is not properly protected, resulting in the credit card being bent or folded, and then the card cannot be swiped. Moreover, if it comes into contact with metal and other objects frequently, it may become demagnetized over time, making it impossible to swipe the POS machine.

2. Entering the wrong password too many times: Bank credit cards require a password to be used. If you enter the wrong password more than three times in a day, the credit card will be automatically locked. This is also a credit card issue. The reason why the card is abnormal.

3. The credit card is frozen or reported as lost: If the cardholder has overdue behavior, cash-out behavior, or other unreasonable behavior with the card, the bank will freeze the user's credit card. If the credit card is lost and the applicant reports the loss, the credit card cannot be used in this case.

4. Credit cards are risky: If the applicant's credit card information is accidentally leaked and obtained by criminals, the user's credit card may be stolen. This is also the reason why credit card abnormalities occur. one.

5. The credit limit is limited or the single transaction limit is limited: The credit card has a maximum credit limit or you have set a maximum limit for a single transaction. Then when you make a purchase, the credit card limit exceeds the credit card limit. If there is a limit, it will also remind you that the card swipe was unsuccessful and a card exception occurred.