Why can't my Unicom mobile phone number receive the Fetion registration verification code?

Unicom's mobile phone number has been registered to use Fetion. .

I'm sure I can receive the Fetion registration verification code.

If not, there are the following reasons:

1, server delay.

2. The landlord's mobile phone blocked the verification code message. . .

The landlord can try to change someone else's mobile phone.