Traffic Management 12 123 What is the reason why Unicom users can't receive the verification code when they make an appointment for the exam? How to solve it?

You can't receive SMS or verification code due to the following reasons:

First, you can check whether the mailbox is full first. If it is full, please delete some information.

Second, you still can't get it after deleting it. You can change the machine or card to see if it is a hardware factor;

Third, after eliminating the above reasons, we can try to see if it can be received in other places to see if it is the reason for the weak local signal.