Ideas
Suitiepie
1 month agoNew Spectator
I had this issue and fixed it.
I exited the game.
went to C:\Users\[User Name]\Documents\Electronic Arts\The Sims 4\
renamed my UserData.lock to _UserData.lock
Started the game again and was able to save my lots.
The problem lot, when visited, was without furniture, so I am guessing the issue for me was in that lot.
I hope this helps you as it did me.
[Edit]Gues I double posted, I thought I was posting in a new thread, sorry.