Shutting down or restarting your iPhone can be a tricky maneuver. Assuming you have an iPhone X or later, you normally hold down the power button and one of the volume buttons at the same time. You then have to swipe across an on-screen button to power off. To restart your phone, wait a few seconds until it’s completely off, then hold down the power button again until you see the Apple icon pop up on the screen.
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