My Apple phone can't make calls or answer phones, and can receive short messages without any hints, but

The common reasons why mobile phones can't answer calls and their solutions are as follows:

[1] Check whether the mobile phone is in arrears, and suggest to pay for recharging;

[2] Check whether the mobile phone is set with call forwarding, flight mode on and call barring. Suggest canceling and try again;

[3] Check whether the function or signal of the mobile phone is normal, and suggest to change the mobile phone or try again;

[4] If roaming to other places can't be used, it is recommended to check whether the local network signal is normal and whether roaming permission is enabled for this number;

[5] Try to restart or change the phone to see if you can answer the phone;

[6] Take the mobile phone card to the local business hall for testing or replacement.