If you don't sign, you can call the customer service phone of CCB, and the bank will help you adjust the bill. If you verify that there is no pos bill, you can refund the money to your account.

Don't worry about this situation, because sometimes there will be problems in data transmission, which happens occasionally. As long as there is no bill and no signature, it should be verified. The next time you have an outstanding bill, contact the bank as soon as possible to see if it has been debited, because there is a time limit for bill transfer.

Legally speaking, passwords and signatures are legal consumption only if they are available, and the lack of one is the illegal operation of income makers.