How to troubleshoot an iPhone 7 that has black screen issue (but Home button is lit)

If you're certain your iPhone was not physically harmed or destroyed before it died, there's a strong chance you'll be able to resolve the issue on your own. There's a chance something went wrong during or after the upgrade. At this point, we'd like to believe that your gadget has merely met an issue it can't handle, and you must assist it in recovering. To do so, you'll need to restart it from scratch. Here's how to do it:

1. Hold down the Power button for a few seconds.
2. Hold the Power button down while pressing and holding the Volume down button on the left side of your iPhone.
3. When the iPhone turns off and on, hold both buttons down; release both buttons when the Apple logo displays on the screen.