Unicom's mobile phone secondary card can't receive short messages.

-Hello! According to your description, I suggest you try the following methods:

1. Try to insert the card again, and the phone will be turned off and restarted.

2. Check whether the memory of the mobile phone is full and whether the SMS blacklist is set.

3. Check whether the number of the SMS center is correct. View path: SMS-Menu-Settings-Information Center.

(The number of the national service center is different, please consult the network operator for details. )

I hope I can help you!