There is a signal, but the mobile phone can't make a phone call or send a text message.

First, the common reasons why mobile phones can't answer the phone 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.

Second, the mobile phone can't send SMS processing method is as follows:

1. You can change your mobile phone to see if you can send and receive short messages.

2. If you can send and receive short messages, I suggest you plug the card back into your mobile phone and send yourself a short message to see if you can receive it.

3. If not, I suggest you check whether there is a problem with the sim card;

4. Check whether the number of the SMS center is set correctly;

5. Bring the mobile phone card to the local business hall for testing or replacement.