A very common problem arises when during the calls, an incoming call arrives. In the absence of any appropriate mechanism, it will not be possible for the mobile users to know about the incoming calls.
Android has a feature to inform the users about the incoming calls while they are busy with some other user. You may activate the feature at your own but if you feel any problem, you may see the instructions.
1: Tap the icon of the ‘Phone Dialer’ on the Home screen of your Android 5.1 Lollipop device to open up the ‘Phone Dialer’ app screen.2: Tap the settings button, placed at the top right corner of the ‘Phone Dialer’ screen. It will open up a popup menu.3: Tap the ‘Settings’ in the popup menu.4: At the ‘Settings’ screen, tap the ‘Calls’.5: At the ‘Call settings’ screen, tap the ‘Additional settings’.6: At the ‘Additional settings’ screen, see the ‘During the call, notify me of the incoming calls’ is not checked, i.e. not activated and enabled.7: Tap the ‘During the call, notify me of the incoming calls’ to check and activate.From now onward, a beep or vibrate will inform you about the incoming call, depending upon the Android device.