Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello 093S-Shirahama, Natsu,
Welcome to Microsoft Q&A forum.
It's unfortunate to hear that your account has been hacked. Based on your description, this means the log in email address has been changed. This is bad news since the account in this state is most likely unrecoverable.
Please note that this is a user-to-user support forum. Moderators, contributors including external Microsoft employees cannot directly intervene in Microsoft product features or access back-end systems. Our role is limited to providing technical guidance on reported issues, requests, or ideas. So if the form the previous user use doesn't work, you can try another form at aka.ms/recovermyaccount if that doesn't help either, unfortunately there nothing more we can do.
Thank you for your understanding.