Download the firmware and reload it to your printer.
https://drive.google.com/file/d/1Na0WDn-uClkr9S-rwjViEQa3RgR_RT3i/view
A loose connection can cause display-related issues. Carefully unplug and then replug the display cable.
Remove the bottom cover by following the steps shown in this video.
https://youtu.be/zC8LA6qXsZ8?si=mflg46uAwGhNVKHL
Power on the printer and check if the indicator light on the motherboard is flashing.
Generally, about 20 - 30 seconds after powering-on, the indicator light will start to flash.
Contact the ELEGOO technical support team and provide us the picture of the motherboard indicator lights.
The status of these lights can give us very important clues about what could be wrong.