Just Came Back After Over A Year - Freighter Has Locked Me In

I've been away for well over a year, but I logged in to find myself on my freighter unable to get to the docking bay. All of the old corridors that went from the bridge to the docking bay are gone and I can't leave the ship or figure out how to build a path to the docking bay. I can see the icon for my ship, but how do I get to it?

I need to get down at least one level, maybe more; the ships are definitely beneath me. There used to be a sloped hall, but it's all been deleted and I can't seem to add the new ladders or anything that will take me down. I can only build corridors on the level I am currently on.

I'm very confused because I am also having to re-learn the controls and what everything does. Is there an easy way to get to my docking bay?