Skeletal Mesh Imported from Blender - Lighting Problem

As you can see from the preview, I have an issue where my skeletal mesh receives shadows separately, as if the lighting wasn’t acting in a unified way on the mesh. I made this model from cubes in Blender, and simply joined them and made a UV out of it. I’m not sure if this is enough details, but I’m tearing my hair out on this problem and I’m not sure what it is.

World placement is irrelevant; it looks like that even on the skeletal mesh editor. I’m not sure if this problem is Blender-related.

What I want to happen is for the lighting to treat the mesh as a single object, and not somehow split the shadow into the separate meshes it used to be.

135345-lightmap+problem.png