Microsoft ファイルのホスティングおよび同期サービス。
Hi!
Could you send me a photo of that multiple-account message in OneDrive? Please black out any personal information in the image; I only need to see the error message. There are two versions of OneDrive for Mac. You might have both versions installed, with your account linked to both, which is triggering this message. This doesn't mean your account is duplicated.
https://support.microsoft.com/en-us/onedrive/why-do-i-have-two-versions-of-onedrive-on-my-mac
If you can't send a photo, send me the exact error you received.