This happened with an old iPhone of mine, I performed a hard reset:
Apple suggest that you, “should force restart your iPhone, iPad, or iPod touch as a last resort, and only if it’s not responding.” Force Restart, Hard Reset, Force Reboot, all mean the same thing and you will see these phrases used interchangeably.
To force restart or hard reset your device, press and hold the Sleep/Wake and Homebuttons simultaneously for at least ten seconds. After about ten seconds, you should see the Apple logo and can release the buttons.
Apple suggest that you, “should force restart your iPhone, iPad, or iPod touch as a last resort, and only if it’s not responding.” Force Restart, Hard Reset, Force Reboot, all mean the same thing and you will see these phrases used interchangeably.
To force restart or hard reset your device, press and hold the Sleep/Wake and Homebuttons simultaneously for at least ten seconds. After about ten seconds, you should see the Apple logo and can release the buttons.


