Sims lag for ages and don't do anything

My game is broken (I think). I start up the game, everything runs fine. About 10 minutes into the game my Sims start lagging; not doing what they're supposed to do but the time moves forward.
Using the cheat resetSim [name] doesn't help move them along either.

I've tried: 
- repairing the game multiple times, 
- deinstall and reinstall the game, 
- deinstall and reinstall the EA app, 
I ultimately ended up testing clean games/new saves and they didn't give me the same issues. I got rid of my mods months ago before this issue started. 
I'm at a loss here, I really tried everything and it has been months of me trying to fix this. I haven't been able to play the game at all. 

Any advice on how to repair this save?