For some reason, all of the sudden this is as far as i build. I can build the stairs on the right but not the ones on the left. As you can see previously I have built all those stairs in the chlorine pit, but now anywhere past the tile under the right buildable stairs my dup cannot go.
I was trying to build stairs in my chlorine pit. Nothing special had happened. I just all of the sudden could not build in and area i was previously able to.