Why can't Shanghai Smart Security app send verification code?

Shanghai Smart Security app verification code can't be sent out because

1. Interception software is installed in the mobile phone, and the verification code cannot be received. I suggest you unseal the SMS of the application software or try to change your mobile phone.

2. The mobile phone is turned off, and there is no signal for the time being, and it is in arrears or stopped because it cannot receive the verification code and SMS. It is generally recovered within 24 hours after payment, basically within 24 hours. Change your mobile phone number or pick it up the next day.