1. You can call the bank’s customer service hotline to make a complaint. The phone number can usually be found on the bank’s official website or on the back of your credit card.

2. You can complain at the bank counter and ask if the bank has a specific complaint channel, or fill out a complaint form.

3. You can complain to banking regulatory authorities or consumer rights protection organizations, such as the China Banking Regulatory Commission, consumer associations, etc. These organizations can provide more help and support.