Dear respected Jonathan12321nathanoJ,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
I’m sorry you’re having a problem but based on your description we can work together to resolve it.
For the situation you encountered, we deeply understand the inconvenience caused and apologize for it.
As per your description, firstly may I know does the fie is shared? also may I know does all the files stored in your OneDrive account "Open in app "option does not exist when you click the ellipsis?
If possible, could you please go to OneDrive>Settings>OneDrive settings>Show Ribbon>Library tab>Library settings>Advance settings> and check/make sure you selected "Default experience for the site".
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We appreciate your understanding that sometimes the initial suggestions may not resolve the problem very soon. However, we can work together to narrow down and resolve the situation.
Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution.
Appreciate your patience and understanding and thank you for your time and cooperation.
Sincerely,
Waqas Muhammad