1. Insufficient balance: the balance of the bank card is insufficient to pay the required amount, so mobile payment cannot be made. It is necessary to ensure that the bank card has sufficient balance or credit limit.

2. Security settings: In order to protect the security of user accounts, banks will impose some restrictions on mobile payment. For example, users need to make specific settings or authorizations on online banking or mobile banking.

3. Mobile phone binding problem: the bank card is not bound to the user's mobile phone and cannot be paid by mobile phone. You can contact the bank customer service to solve this problem.