bcxyza The errors are coming from OneDrive, specifically the red Xs mean that a given file or folder hasn't been synced. The only fix, other than buying more cloud storage (not recommended unless you actually need it, which you probably don't) is to prevent OneDrive from syncing your files in general. The various options are listed in the first post of this thread:
https://answers.ea.com/t5/PC/CURRENT-ISSUE-Sims-4-saves-user-content-disappearing-PC/td-p/12475370
Let me know if you need help with any particular step.