Examine the battery to be sure it is properly connected and in good condition. If not, replace it with a new battery.

Hold down the Home button, Power button, and Volume Down button simultaneously. Hold until the phone turns off, then release and turn the phone back on.

If the phone is not responding, try connecting the phone using a USB cable to a computer. If necessary, download updated software or restart the computer.

Run diagnostics on the display system and check if the settings for your phone’s display have been changed or corrupted. Be sure to update your software to the most recent version.

If none of the above steps was successful, take the phone to a service center to troubleshoot and repair the issue.