How to fix phone display turing into blue colour

I’ve had a friend that had that issue awhile back. He had a screen protector on and I think he didnt apply it correctly and small particles of dust were on the screen. Then time passed and the screen started having purple and pink on the bottom left corners, day by day it started to spread around all of the display and eventually he replaced the screen. If you have a screen protector remove it asap or you will end up breaking your phone.