Mobile device doesn't ring (No ringing from receiving SMS)

Maybe your device doesn't ring because of the Airplane mode. If you don't see the signal strength, nor the operator's name in the upper-left corner of the screen, but you see a small airplane icon, the airplane mode is enabled.

See the don't know how to enable/disable the Airplane mode guide if you are not sure how to disable this mode.

Maybe the apps volume level is low. All you have to do is to go to the Settings and move the app-volume slider to the right or via the app itself.

Go to Settings and tap on Sounds (& notifications). Move the slider under Media volume to the right as much as you want.

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Note: The screenshots are taken using a Sony Xperia M2, running on Android 5.1.1 Lollipop. The instructions mentioned here might slightly vary from one manufacturer to another.

If your iPhone doesn't ring, but you receive notifications in your voicemail that somebody called you, it's possible that you have enabled the Do Not Disturb option. If you see a half-moon icon next to the battery icon, this option is enabled.

You can disable this option via the Action Center or via Settings:

• Via the Action Center:
  
  Swipe up from the lower part of the screen and tap the half-moon icon.
  
  

  
  
  

• Via Settings:
  
  Go to Settings -> Tap Do Not Disturb -> Move the switch next to Manual to the left.
  
  

     

Maybe your device is in silent mode. All you have to do is to disable it. You can do that in several ways:

• By pressing and holding the power button and taping on the speaker icon,
• By swiping down from the top and tapping on the speaker icon,
• By pressing the volume (+) up key.
  
  

Note: On some older devices you need to change the profile, from Silent to General.

Maybe your device doesn't ring because the call barring feature is enabled. This feature blocks all the incoming calls.

You can disable this feature via the call settings or by contacting the carrier (operator) you are subscribed to.

If your device doesn't ring when you receive notifications from an app, it is possible that its notification sounds are disabled. In order to enable them, you should go in the app's notification settings.

The call diverting feature enables you to divert all the incoming calls from one phone number to another. If you have enabled this feature, you won't be able to receive calls; therefore, your device won't ring.

Go to the device's Call Settings and disable call diverting. If you are not sure how, ask the carrier (operator) you are subscribed to for instructions.