Look to me like your normals are flipped. Try setting material to two-sided and see if renders correctly, if it does your normals are flipped, it is rendering the backside of the faces as if they are the front.
THANK U MAN!! but I didn’t understand why I should make white material two-sided (which is normally displayed), but I made it two-sided and now everything is fine!
Wouldn’t flipping the normal, or inverting them, be a more applicable solution then? if two-sided is not wanted?
…yes, hence th image of flipping normal in blender above