My Retina Display has stain damage, HELP!!!

I dont know how it happened, but somehow my retina display got some weird clear-ish stain damage that is very noticable on a black background. I have tried to clean it with water and a micro fiber cloth like usual, but i think this is not something on top of the screen as much as it is something has like eaten away a part of the screen... I need help! what do i do to solve this aside from replacing the screen... if water and microfiber arent working, what else can i use? I am worried that windex or alcohol will excacerbae the problem, as i suspect it might have been alcohol that caused the problem in the first place, but im not sure... any insight, please? this is driving me nuts