Unicom SMS can only be received if it can't be sent out.

The reasons why mobile phones can't send short messages are as follows: 1. The mobile phone has no SMS service, so you can contact the local manual customer service or open this function in the local business hall; 2. If the SMS center number is not set or set incorrectly, just reset it; 3. The signal is weak, there is no signal or the battery of the mobile phone is insufficient, resulting in the information not being sent normally; 4. Because the system is busy, especially during the peak period of sending short messages on holidays, it is suggested that you try again later or avoid the peak period of sending short messages; 5. The sending format is incorrect. If you send a short message to PHS users, you need to add the area code before the number; 6. I suggest you restart your mobile phone or change it for a test. In addition to the above simple troubleshooting, it still cannot be solved. You can contact the local manual customer service for processing.