Black Grass and Shadow

My problem is that grass looks pitch black.
Problem occurs mostly in this sequence. From MainMenu scene i load Level1, from Level1 i go back to MainMenu and from MainMenu i load Level2 and the grass is pitch black .

I’ve read that it could be a lightmap issue? The terrain does not load the lightmap data.
I have cleared the lightmap data though from “Window->Lightmap->Clear” but the issues still exist

On editor i don’t get this issue , only on my Android device.

any help,ideas how to fix this?

1364724--68160--$blackgrass.png

have the same problem after update… still dont know how to fix =((