Don't worry! There are multiple ways to help you fix the iPhone black screen problem
1. Fix iPhone Black Screen Problem by Hard Reboot
When you find your iPhone won't turn on and becomes unresponsive, you can try fixing the problem by hard reset your device. It is easy to accomplish and here's how to do based on different iPhone models.
For iPhone 7/7 Plus, press and hold the Side buttons and the Volume Down buttons for at least 10 seconds until the Apple logo appears on the screen.
2. Fix iPhone Black Screen Problem without Losing Data
In general, since the iPhone black screen problem can usually be attributed to iOS glitches, the most effective and simplest method to fix the iPhone when finding it stuck on the black screen is to take advantage of a professional iOS repair software
3. Restore iPhone to Factory Settings to Fix iPhone Black Screen
Since most users have reflected that "My iPhone screen is black" from our emails, we will offer another useful way to help to fix this issue which requires using iTunes.
Step 1. First make sure the latest iTunes is well-installed in your computer. Connect your black screen iPhone to your computer and launch iTunes.
Step 2. Simply press the Restore button to restore your iPhone to factory settings if iTunes detects your device successfully and shows the restore option. Remember to restore the backup if you have an iTunes backup.
Step 3. The iPhone will restart once done and get out of the black screen problem. Go ahead and set it up as a new device.