I checked on google and somebody with the same monitor have the same issue.
Its something like this ,but much less noticable than this:

I have 2080 Ti Waterforce Xtreme,this is not issue with GPU. I checked on google and somebody with the same monitor have the same issue.
I tried removing by finger,and its not a dirt,debris etc. As if something wet leaked inside
Its barely noticable when i am playing but still appearing.
Rma or it dissapear itself?