What is the reason why the SMS verification code can't be received?

Unicom number cannot receive SMS verification code for the following reasons:

1, you can first check whether the website supports the mobile phone number to obtain the verification code and whether the mobile phone number is entered correctly;

2. If there is no problem, check whether the mobile phone has blocked the SMS receiving function;

3. If it is not blocked, please check whether the mailbox is full. If yes, please delete some information.

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

After eliminating the above reasons, you can try to test whether you can receive it in other places to see if it is the reason for the weak local signal.