The failure of electronic signature may be due to the following reasons:

1. Your handwriting is scrawled, and the system can't detect what you wrote. It is suggested to write in a standardized way.

There is something wrong with your mobile phone screen, so you can't write your signature in the designated area. It is recommended to calibrate the screen.

3. System problems, resulting in temporary unavailability. I suggest you change your mobile phone to see if it works properly.