CCB consulted the bank's customer service and asked whether the system was being upgraded or the server was out of order. If there is, it will take some time, and it can be used normally after the other party handles it.
If the other person says no problem, it's your mobile phone problem:
1. Please close it and try again.
2. Try to switch the network connection mode.
3. Uninstall the software, download the latest version again and try to install it.
4. Try to restore the factory settings of the backup data.