There are three types of clouds that may cause this problem, but you don’t need to worry about them. Just protect your credit card information.

1. The phone card has been bound to a credit card by someone else before.

2. It may be that the credit card information has been leaked, and someone is trying to operate or steal the money behind the scenes.

3. Someone may have done it intentionally as a prank, but this person must know the card number.