It's quite rare that major performance problems occur on iPhone devices, but what if iPhone stuck, in this article you can find a solution for the screen iPhone stuck, which no longer responds to commands. Force restart.
If iPhone stuck or the screen is black and no longer accepting any commands, follow the steps below to solve the problem.
iPhone stuck? Fix iPhone locked screen.
Force restart iPhone 8, iPhone SE (2nd or 3rd generation) or newer.
1. Press and quickly release the volume up button (volume up).
2. Press and quickly release the volume down button (volume down).
3. Press and hold the side button (the lock button, on the right side of the device) until you see the logo Apple.

If the logo does not appear Apple on the iPhone screen, it most likely does not have a charged battery or it is a more serious problem.
Force restart iPhone 7 or iPhone 7 Plus
1. Press and hold both the side button and the volume down button (volume down) until you see the logo Apple on the iPhone screen.

For models iPhone 6s and earlier, inclusive iPhone SE (first generation), press and hold both the button Home, as well as the side button or the top button until you see the logo Apple.
This method will force a restart iPhone and everything should be back to normal.
If iPhone doesn't respond to these commands and won't start, it means you have to check if iPhone it is still under warranty and contact an authorized service Apple.