Hey @Joan P.6, I hope you're well today!
From what you mentioned, you're working on the file locally through the Microsoft Word app, right?
When you edit the file through the local apps on your computer, real time collaboration isn't currently possible.
As you've seen, sometimes when editing a Word file, the app creates a temporary file which you've seen with the change in file name and location. You can find out more info on why Word creates temp files from here.
To collaborate in real time, you'll need to use the Microsoft Office Online integration. The steps for this is outlined here.
Let me know if you have any questions!
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