@0119Person
Step 1. Rename The Sims4 folder in the Documents to "The Sims4 old"
Step 2. Fix the game in Origin
Origin/Library - right click on TS4 - option "Repair game"
You have to wait until Origin will fix all packs, not only the base game.
Step 3. Turn on the game - a new game folder will be created and you will have two - one old, one new
Step 4. Check if you still have this problem in the newly created game folder. Start a new game with a random sim. Save it, quit the game and try open the game.
If it worked:
Step 5. Delete in the new game folder following folders:
"saves" and Tray.
Step 6. Go to "The Sims 4 old" folder and copy - your "saves " folder.
Step. 7, Paste this folder in a newly created game folder.
Check if working now with old saves.
If yes:
Step 8. Do the same with Tray folder and TrayDeleteItems file if you have this file in the old folder
Step.9. By the way, you can check if your mods - if you have any - are up to date. If you don't have any mods - skip this step
Step. 10. If all is OK - delete The Sims4 old folder. Now you will have only one game folder - I hope - working properly.