Some people are complaining that the button used to put their iPhone or iPad to sleep, and to wake it up, isn’t working in iOS 10. To fix it try pressing and holding the Sleep/Wake button, and if you see a “slide to power off” message, do so to turn your device off, then turn it back on. If you can’t turn it off, force restart by pressing and holding the Sleep/Wake and Home buttons for ten seconds until you see the Apple logo. On iPhone 7 and iPhone 7 Plus, press and hold the Sleep/Wake and Volume Down buttons. If that still doesn’t work, contact Apple Support. If you have an iPhone 5 you be be eligible for a replacement.