***The weakness of the network in phones is the most common reason for the problem of not hearing the voice of the caller. If the network is weak at the other end, ask him to change his location. If your network is weak, choose a better place where the signal strength is higher***
***Sometimes the problem of not hearing the caller's voice occurs, because your call volume is low, and one of the sound control settings on your phone is the call volume settings, which you can access through the control buttons***