Why does my door look like this in game?

I've never made a cc door before, and there doesn't seem to be any tutorials about it (hopefully one day there is) so I thought to post here. When my door is placed randomly, it looks fine. When I place it against a wall (not a room), it still looks fine. The issue is visible when I place the door against a wall of a room. I'm not sure why this is happening nor do I know how to explain it, but any help is veryyyy appreciated. Here is the link to images of the door: IMGUR