If the overdraft is overdue, you can call customer service to apply for unlocking. The reason why ICBC locked the 4000 credit card after returning it is because overdue overdraft will not only result in liquidated damages and interest. It will also affect the credit information, causing banks to freeze their credit cards, and the credit cards are locked, so cardholders need to repay as soon as possible. After changing the money, call the customer service phone of the credit card center to unlock the bank. Most banks stipulate that three consecutive credit card input errors will be locked, such as China Construction Bank, Industrial and Commercial Bank of China and China Merchants Bank. Therefore, customers must pay attention when spending by credit card. If you really can't remember the password, in order to prevent the card from being locked due to the wrong password, the customer had better find a way to retrieve the password first.