Lighting Issue

I dont know if this is the right place to post this sort of thing, but i need an help.
Recently i’ve begin to develop a game. But i’ve got some problem, with the lighting.
I use the version 4.12.5 and when i build the lighting, my mesh look like this: MEGA
I’ve tried to export the lightmap from Maya, but the problem persist. So I’ve tried to generate the lightmap from Unreal Engine 4, but the problem persist.
If anyone can help me, I would be extremely grateful.
Sorry for my english