GPU lightmass 4.27 bakes black object

I am using GPU lightmass for my bakes in 4.27 and after the bake some of my objects are fully black. I am aware of lightmaps and all my objects have a UV channel for texturing and a second channel for the lightmap. I have checked the lightmaps and made sure there are no overlaps. I have played with the lightmap resolution and even tried crazy values like 1024 (for a doorhinge). No change. I have checked the normal direction and collapsed the stack in max. I even tried exporting out of maya after deleting history.
I have had this issue before and after remodeling the problem went away. But this is a good model, no n-gons or anything so this shouldn’t be a problem.

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You might have flipped the faces–for example if you used 3ds Max and you used mirror and clone to duplicate the hinge to the other side, then it would have actually flipped the faces, you’d need to go and reset X-Form before exporting to UE4

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I have the same problem but only in android devices with Mali GPU.
Any solutions?

I know this is a very old thread, But I have one last question. Correcting the normal fixed issue for my house models. But the foliage meshes have transparent planes so always one side will have the wrong normals. How can I fix it?