A Microsoft file hosting and synchronization service.
Hello, Alalea
Thanks for your reply.
In individual user posts, they described a similar situation: they could edit files in their own OneDrive folders but not in shared folders. This situation is indeed related to specific accounts.
As I mentioned in my previous reply, you can let your fiancé create a new Microsoft account and test if he can edit documents in the shared folder with the new account. This will confirm whether it is an issue with his OneDrive account.
Due to the limitations of this forum, we are not authorized to handle issues related to specific accounts. If it is indeed an issue with his account, I sincerely recommend that you contact OneDrive Support.
To contact them: Log in to OneDrive.com with his account, then click on this link: Email OneDrive Support
Best wishes,
Lucia Wu - MSFT | Microsoft Community Support Specialist