Samsung A8 suddenly can't make phone calls or send text messages. Why?

The following actions are recommended:

1. Turn off the phone again.

Try to insert the SIM card into this machine.

3. Check whether the mobile phone is equipped with software such as security guards or incoming calls, uninstall it and try again.

4. Whether the attempt to update the version of the mobile phone system has improved.

5. Back up mobile phone data (phone book, SMS, multimedia files, etc.). ) and restore the factory settings.

If the problem still exists, it is recommended to send the mobile phone to the nearest service center for testing and maintenance.