Cannot click on second floor

So my girlfriend and I have spent a crazy amount of time building up an enormous house. With a ton of items. So I hope rebuilding is not the only solution because that would really really suck. And be so many hours wasted.

But here is the issue....

The game has been running just fine this entire time. And out of the blue, we cannot select the upper second floor to move our sims up there. Nor select like the bed and have them go up. They just cancel out. When I click the floor, it doesn't respond with your typical action prompts. It merely does nothing when clicked. Nothing is in the way. No Mods. Not sure what could have caused this so suddenly. I do have it on the gallery if anyone can give it a go. I tried transferring it to a different lot, but same results. The only change we made we can recall between it working and not working is adding a floor vacuum roomba thing. Which we have deleted since and did not solve the issue. We are stumped and are very sad we cannot have normal play after all the work that was put into it.

If anyone has had similar experiences and has ideas on things to try first lemme know. Otherwise I shall send you the uploaded gallery lot.

Thanks