Overlapping lightmap UVs by (x)%

I get this error a few times when I try to build lighting, so the number it tells me varies based on which of the errors it is. This is happening with a basic lightbulb model I made- it uses a black and white texture to specify where the material should glow. I’m not sure what lightmap UVs are, I didn’t set them up myself in maya or the editor, so a bit of background information would be fantastic if you use certain terms I might not understand. Thanks!

Ah! I realized why this is happening.

“By default, the first set of UVs (index 0) of a Static Mesh will be used when generating lightmaps for static lighting. This means the same set of coordinates that is used for applying materials to the mesh will also be used for lightmaps. This is quite often not ideal. One reason for this is that the UVs used for generating lightmaps need to be unique, meaning that each face of the mesh must not overlap any other face within the UV space.”

So- there’s that. Yes, some of my UVs share the same space. So what am I supposed to do now? Also, say I have a textured area of a mesh. If I duplicate it, does it create another UV shell on that same spot, or does it simply use the UV shell of the original mesh?