How do I fix this weird pitch black model lighting

[robust iron]

I have been working with this model that appear pitch black in my map and no matter where I put lights it stays pitch black. but if I put it in another map or if i shine my flashlight on it it becomes not pitch black, I have been messing with it for hours and I have been unable to get it correctly lit

when I select mat_fullbright 1 it gets lit correctly, but when I select mat_fullbright 2 it appear pitch black when most other things appear grey, so something is off with something about the object