Digital RMB cannot be bound to a bank card, which can be solved in the settings. There is no online merchant bank in the bank card that supports binding in the digital RMB APP, but it can be bound in Alipay. Open Alipay, click "My", select "Digital RMB", click "Bank Card Management", click "Add", enter the bank card number of the online merchant bank, enter the mobile phone number reserved by the bank, click the agreement and bind the card, enter the verification code, and click "Next" to add the online merchant bank card successfully. If the balance is insufficient, you can deduct money directly from the online merchant bank, or you can add the bank cards of other banks.