1. A prompt box with wrong phone number format appears. First, you should check whether the telephone number is entered correctly. Sometimes it is inevitable to write the wrong number because of personal negligence.
2. If the number is correct, there is still a prompt with wrong format, which may be because the current software version is too low. You can reinstall this software, preferably uninstall it.
3. It may be because the input method is adjusted to Chinese input method, and then full-angle input is selected. Switch to the half-angle input number, or switch to the English input method, and then enter the mobile phone number.