Managing personal Outlook.com account settings, security, and privacy
Hey there, David Wu
I am sorry to read about your current situation with your Microsoft account being compromised.
When attackers gain access to the Microsoft account, they replace your security information with theirs to prevent you from gaining access to your Microsoft account using the forgot password method. They then change the password and the Microsoft account alias. This prevents you from gaining access to your account, due to the account no longer existing when you use your old alias (sign in email address).
Unfortunately, in order to complete the Microsoft account recovery form, you will need the new account alias they have used for your account. Please can you go through your alternative email and check if you received an email from Microsoft notifying you of changes to your Microsoft account. This will allow you to find what they have changed the alias to, which will allow you to complete the account recovery form.
If you can't find the email address, you won't be able to complete the Microsoft account recovery form. Please can you tell me if you used your account for gaming on Xbox or Xbox services?
I am sorry I can't bring better news with regards to your current situation,
Nathan