Hi @Neha, things have stabilised today.
Myself and my teammate can both now upload and download files through Finder and they do sync to the cloud. Interestingly, no other team members were effected even though they use the same library.
So, we are now back to the initial situation - my teammate can upload and download files but anything new she creates or changes (any file type) is marked with the (-) sign. She is the only one who can see the (-) sign, I can see, download, open and edit the files either from Safari or from my own hard drive (synced to my laptop).
To answer your questions.
I can't check other libraries now - that'll have to wait until Monday.
Yes, offline availability is enabled.
MacOS 12.01
OneDrive app is standalone 22.012.0117.0003
At no point has there ever been any messages in the OneDrive icon in the menu bar for any of us. My colleague's menu bar icon says "OneDrive is up to date" at all times, despite the presence of the (-) signs across many directories and files.
Thanks!