In the image attached below, all of the walls have the same material applied to them. But the middle portion of the wall doesn’t seem to be taking the color of that material. It is showing up the exact color of the light in the scene. The light isn’t any closer to that part of the wall than it is to the other two parts, so I don’t know why it would be reflecting that much of the light back when the other two aren’t. It doesn’t seem to have any of the diffuse color of the material at all. I’ve checked all of the settings and I don’t see a difference between the middle part and the outer parts but I’m hoping someone can tell me that I’m missing something. I really want my wall to be one color.
Any chances your normals are flipped on that polygon?
If so what you’re seeing is just the “sky”. Is this part visible from the outside.
You could fix that either by recalculating normals in the import settings of the model, or directly in the 3d program you use.
If they just planes, see if this one is simply flipped inside out!