Iphone suddenly can't send text messages

1, mobile phone stopped using SMS because of arrears.

2. The short message can't be sent because the signal around the mobile phone is poor or the signal is covered.

3. The 3.SIM card is broken, and information cannot be generated.

4. There is something wrong with the mobile phone system. It is recommended to shut down and restart or restore the mobile phone system settings.

It is also possible that there is something wrong with the hardware of the mobile phone, which can be solved through the maintenance of the mobile phone.