look for R68 COIL on the board..
u might need to take the top plate off
give a good clean around that coil with cleaning liquid solutions..
clean the lcd connector.
make sure lcd works and is ok..
put everythng back togethor and put the phone on charge straight after assembling..
if didnt worked.
replace the coil 1000% tested and fixed 1000 of those problems..
You can try these:
Step 1: Check the connectors of screen whether they loosen or not.
Step 2: If the connectors hold in place, take a good look at the LCD with digitizer flex cables, it is the most vulnerable part. If they have been worn, you have to replace the whole LCD screen with digitizer.
Step 3: If the flex cables are intact, the problems still exist. You need to replace the complete LCD screen with digitizer because the LCD is damaged.