Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
I am having the exact same problem and your solution by going to mysignin.microsoft.com also asks for an authenticator code. I am only able to write this to you from another microsoft account that I have. If i did not have this other account, I would not have been able to reply to this without needing to sign-in which again requires an authenticator code. Catch 22 after Catch 22 after Catch 22. My only solution that I have figured out is to go to my credit card company and cancel the subscription through stop payment. Your post is helpful, except it doesn't work because it requires a sign-in to authenticator, which I don't have. This is so incredibly frustrating. I wonder how many people have cancelled their accounts because they can't sign-in and as a result can't even get help to solve this problem. I bet it is a large number.