Unicom's mobile phone can't make a call. what's up

1, check whether the number is in arrears, and suggest paying 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. It is recommended to change your mobile phone or location and try again. 4. If you can't use it when roaming to other places, it is recommended to check whether the local network signal is normal and whether the roaming authority is opened for this number; 5. Try to restart or change the phone to answer the phone; 6. Bring your mobile phone card to the local business hall for testing or replacement.