What to do if iPhone 7 power button not working?

Apple introduced the new iPhone 7 and iPhone 7 Plus to us on 7th September. Along with it came the all new Apple Watch Series 2 and AirPods. The iPhone 7 line is outstanding successor and It has already gotten solid reviews from critics and the general public. It is definitely one of the best phones on the current market but like any phone, flaws exist. Besides the controversial missing headphone jack, what else did the users complain most?  –The iPhone 7 hard button issues.
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1.Make sure your iPhone is battery alive first
There is no doubt that the power button won’t work without power, so check the rest battery juice first or simply apply a qualified charging cable to get your iPhone 7 recharged. If you don’t see the charging screen within an hour, or you see the connect to power screen, check the jack, USB cable, and power adapter. Make sure that everything is plugged in firmly, free of debris, and not damaged. You might want to try a different USB cable or charger.
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2.iPhone 7 is already powered on, but it gets stuck on the Apple logo screen
It means your iPhone 7 stops on the startup process, try to connect your device to a computer and open iTunes, then force your iPhone 7 restart with pressing the power and volume down buttons at the same time. 
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3.iPhone 7 Power Button Not responding at all
iPhone 7 introduced a new solid-state Home button which no longer physically depresses but instead is a software-driven sensor. It appears that if the iPhone 7 doesn’t detect a working home button, a digital version of the button will appear on screen. However, there is no virtual power button to get survived when the physical power button stops responding.
If the iPhone 7 power button is not responding at all, this solution might not work either. Chances are there might be software or iOS defects, so keep your iOS updated to the latest version if your iPhone 7 is functioning except the broken power button.
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4.iPhone 7 Power Button getting loose
It might sound impossible for a brand new phone, but we do received some similar comments from our readers. Unfortunately there is no good advice except for a replacement on warranty period. When your iPhone 7 power button not working at all, which means you can’t force your device to get hard reset due to loose, stuck or broken power button, in this case you have to contact Apple support for help.