1. The message was not sent successfully: Please confirm that the mobile phone number and SMS you provided are correct, and wait for a while to see if you will receive a reply.
2. Peak period: If information is sent during the peak period of alarm, it may cause delay in reply.
3. The system is busy: sometimes, the server of 12 1 10 may not be able to process short messages due to network problems or system maintenance, or it may not be able to reply in time.
4. Special circumstances: If your message involves personal safety issues, such as calling the police, 12 1 10 may choose not to reply to the message, so as not to bring unnecessary trouble to the alarm.
If you haven't received a reply for a long time, you can try to resend the message or call 12 1 10 for consultation.