When the DNF security mode is released, the information sent by the mobile phone (Unicom card) to his designated number will never be sent. Just send it to others. What happened?

1, the port you sent is incorrect. It belongs to the exclusive port of other operators and can only receive the information of the corresponding operators, just like the mobile phone number can't send short messages to 100 10;

2. Your number itself is limited in short message function. In some areas, special port instructions will be filtered. Please contact customer service.

3. Similar to possibility 2, the problem lies in your mobile phone. Check whether there is security software to intercept short messages sent to special ports.