Control the mobile phone to send short messages

This means that the anti-theft system of the mobile phone is activated, that is, the phone number set in the anti-theft system of the mobile phone is yours, which means that the anti-theft system of the mobile phone finds that the SIM card of the original mobile phone has been replaced, so it automatically activates and sends a short message to the original set number to inform that the SIM card has been replaced or the mobile phone has been stolen.

Of course, it is also possible that a liar lied to you.