Before trying any of the following steps, make sure you have disabled any screensaver settings or active display modes on your phone:

1. Reboot your phone by holding down the power button until it turns off. Once it has completely powered off, turn it back on by pressing the power button.


2. Check for any pending software updates that might have been missed on your phone. Updates are generally used to fix bugs, including issues with the display.


3. If your phone has a replaceable battery, try replacing it with a new battery. If the issue persists, then the battery is not responsible for the issue.


4. Try factory resetting your phone to the original settings – this should fix the issue as long as the hardware is still functioning properly.


5. If all else fails, most likely the issue is with the hardware, specifically the display. You may have to take your phone to a smartphone repair store.