Light Bake issues, don't know what settings to modify

Hm, don’t you think 10 pixel is enough for that little stripe? How the light bake looks on it is really fine for me, i just have problem with this spot that generates. Actually i have this piece repeating 8 times, and this issue looks exactly the same on all of them. Once I baked a 4k map on this object, and this spot was still there, just higher resolution.