Shell app can't receive SMS verification code

Network delay. Due to poor network or weak signal, the SMS verification code cannot be received in time or not. You can check the network delay or server communication delay, and switch the flight mode to trigger the network to send SMS again. Verification code is the abbreviation of Turing test to automatically distinguish between computer and human, and it is a public * * * automatic program to distinguish whether the user is a computer or a human.