Some Apple iPhone owners might experience a problem with their devices where vibrate no longer works as it should. The problem is quite common. Here are a few things to try if you are experience this issue.
Ensure Setting is Set Properly
From the Home screen, select “Settings” > “Sound” and ensure that “Vibrate on Ring” and/or “Vibrate on Silent” is set to “On” (green).
Tap to Loosen Vibrate Device
Sometimes the vibration device inside the phone can become stuck. A gentle tap to the back and sides of the device will often loosen it up. Some users have suggesting calling the iPhone from another device while tapping the iPhone.
I’ve seen where it takes a while of tapping to fix this issue. Keep at it and it should work.