I m using the baked GI mode with directional light set to baked and after baking lightmap, these edges started to appear on the Mesh. Here is a screen…
Well yea, I did some research and found a workaround. Its maybe a bug in unity since ever that the mesh option “Generate Lightmap UVs” isn’t perfect and Generated UVs by unity caused this to happen.
What I did is just went into my modeling software (Blender) and made an extra UV for lightmap. Now u can see, it worked well. Hope it helps anyone in the future there 
