Sims 4 build mode not working properly?

I've got an empty lot, and when I use the wall tool to build a room, there's no ceiling. I thought it might have just been a glitch, so I went up to the next floor and added another room on top that was the same size, so I could just use the top floors ground as the bottom rooms ceiling, but the top floor had no floor AND no ceiling. Anyone else have this happen? Since the recent update I've had a lot of problems with the game, in fact the reason I'm even building anything at all is because every single lot in every world literally just disappeared. There was an orange exclamation mark over the top of every building on the map, and when I went into build mode on any of them, they would be completely empty. So any way to fix that would also be very handy.

I have no cc or mods or anything like that