Hi Isaid. I'm Greg, awarded MVP for eleven years, Volunteer Moderator, and Independent Advisor here to help you until this is resolved.
OneDrive may have made changes to Settings without your knowledge, so go over them now to decide if they are what you want:
If the Folder Protection Backup is chosen in OneDrive Settings > Backup Tab, then the User Documents, Desktop and/or Pictures folders will be moved into the OneDrive folder to sync to OneDrive and (if you want) your other devices. See Folder Protection details here to understand more and make changes if desired:
https://www.tenforums.com/tutorials/116029-turn...
In addition if you go over the 5gb file limit and don't buy more storage in OneDrive online settings, OneDrive will not sync the files any longer - and this might be the reason it is deleting them, although this would be the first case of this I've seen in forums daily for 12 years.
Another setting designed for smaller hard drives removes files from the hard drive and stores them only in the cloud if Files On Demand is chosen in OneDrive Settings. This feature is described here:
https://www.pcworld.com/article/3233488/windows...
If you don't want Files on Demand then after disabling it, allow it to download all the files back to the hard drive before disabling Backup Folder Protection.
Also in OneDrive Settings > Settings tab tick the boxes to have OneDrive Warn and Notify you before deleting any files. This is the default behavior unless these boxes are unchecked, and you should always be able to find these files in OneDrive.com online Recycle Bin until you delete them yourself or approve their deletion.
I hope this helps. Feel free to ask back any questions and let us know how it goes. I will keep working with you until it's resolved.
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