I think you should start your Mods folder from scratch. It sounds like there are possibly multiple issues here.
First, make sure that OneDrive and other syncing programs aren't affecting Sims 4. See https://forums.ea.com/discussions/the-sims-4-technical-issues-pc-en/current-issue-sims-4-savesuser-content-disappearing-pc/11838402
Then delete the current Mods folder or move it (not copy it) to your desktop. Delete the file called localthumbcache.
Start the game and exit to make a new Mods folder. If you can't find the new folder after, see https://sims4.crinrict.com/eng/2018/07/how-to-find-your-user-folder/
Mod & CC Issues: START HERE | EA Forums - 5035292Add mods into the new Mods folder in small batches, not all at once. Check the broken and previously broken mods lists to help avoid adding broken mods. Not all current versions of mods work. See Mod & CC Issues: START HERE | EA Forums - 5035292
