My co worker has a spreadsheet she updates everyday. It is on a folder on her OneDrive which is shared with me. If I open the file in the webapp I see the latest file but if i open it on the desktop app I see the file as at 27-Sept-2022. On the desktop app I am unable to make changes and merge with her file. I am using Excel 2019 and Office 365.

Can't understand what's going on because it was working perfectly a couple weeks ago.