Hi John,
From the screenshot, I suppose you just sign into one Office 365 account . I'd like to explain that in this scenario , there are no such "Remove" and "Manage" buttons. If you want to disconnect the connected services, sign out your Office 365 account will do the trick. Meanwhile, the "Remove" button will appear if you add additional accounts via clicking Add a service. Here is a screenshot for your reference:
Let me know if the answer addresses your questions.
Thanks,
Sky Pei