VR - "Stretching" effect on MirrorMaterial using Planar

Greetings guys, so i got this weird problem with my planar reflection.

It has this weird stretching outside, duno how to explain it.

Inside the planar settings i played around with the distance from plane fadeout start / end but didnt worked that well.

In game its kinda around the visible screen size so not just on the left, couldnt get a better screenshot of it.

I dont know if this is a typical VR thing and if it can be fixed that easy, but can anyone tell me what it causing this or more important how to fix this?

Apreciate it <3