Files mysteriously deleting from my computer, moving themselves to the cloud.

My files keep becoming unopeneable. I have to click 'download now' under the right click menu to get them from the cloud to open them. Shortly after I download them and have them open im greeted to a popup reading: "The document "XXX" could not be reverted. The file doesn't exist." and in the subheading: "This document can no longer be used because its file has become unreadable, so it must be closed." After clicking download now again I can reopen and use the files, until they shut down once again minutes later.

For posterity, I've had them open at the same time and they both simultaneously get the error message. I've also tried removing them from my iCloud drive and replacing them, duplicating the files, and for oen file I even took a screenshot of the content and tried using the screenshot instead, only to be met with the same problem.

Just wondering if anyone has encountered the same issue, or has any information as to why this happens.

PS. I tried attaching screenshots but the forum won't let me. If that could help im sure I can arrange you receiving them.

Thanks