This guide will let you know how to turn off phone calls in Grand Theft Auto 5 Online.
The first thing you will need to do is bring out your in-game phone and go to settings. Navigate to the Vibrate option and turn it off.
After that, go to Ringtone and set it to Silent. Then go to Invite Sound and turn it off.
After that, close the mobile phone and press the Esc button to open up the setting window. Go to the Notification tab on the left side and turn off all the notifications. You have to set the Message Frequency to 30 Minutes. It will help to minimize the call notifications in GTA.