1. Your mod is on the stealth mode.
2. the firmware got damaged with frequent operations of the abnormal shutdown.
3. The screen is broken.
1. Please check whether it is at the stealth mode firstly (When the device is on, click the fire button 3 times to enter the menu setting to turn the stealth mode off.)
2. Please try to upgrade it if there is firmware updating for your mod.
3. Please mind that while replacing the batteries, to power off the mod firstly by menu.