How to force restart iPhone 8/X
 

To force restart (hard reset)the iPhone 8/X, press and release the volume up bottom, press and release the volume down button,and press and hold the power button until your device reboots, then release.all the three button presses should be done in relatively quick succession. After holding the power button for about ten seconds, the iPhone will restart.


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How to Force Restart or Hard Reset the iPhone 8 / 8 Plus and iPhone X?

Press and quickly release the Volume Up button.
Press and quickly release the Volume Down button.
Press and hold the Side button (aka power) until you see the Apple logo.
Powering off regularly still requires holding down the Side button for a few seconds until the "slide to power off" prompt appears. In iOS 11, there's also a "Shut Down" option in the Settings app at the bottom of the General menu.

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