icloud Drive not syncing all files from Desktop & Documents Folders

On my main iMac running macOS Monterey Version 12.4, I have iCloud Drive enabled, along with Desktop & Documents Folders without the Optimise Mac Storage option enabled (it is disabled).

I've got two laptops, one older and one newer M1 model, set up similarly. Irrespective of that, I'm using iCloud on the web to confirm things.

A lot is syncing, but a big portion of my documents are not. In the finder, I can see the iCloud status next to the unsynced files as a dotted outline of a cloud--presumably meaning "waiting to sync."

I couldn't get anything to sync previously, and thought that it could be a permissions issue. I couldn't get the sync to work with permission for my user account on those files, so I changed all the permissions of everything in my Documents folder to admin, Read & Write. That seemed to help with most of it, but as I say, not all of it.

This is a screenshot of permissions for a file that won't sync.

If I try to change everyone to Read & Write, it changes for a second and reverts to Read only by itself.

I can only guess that my syncing issue is one of permissions. I think I have plenty of space left in iCloud.

My Documents folder is 118,85 GB while only 58 GB is being used by documents in iCloud Storage. Anyway, I'm not getting any warning that it's an issue. I should only need another 61 GB so am in the safe zone.

Could I help some help here as I'm very frustrated at the moment.

Thanks,

B