Hello Jasper Pallette,
Welcome to Microsoft Q&A forum.
I understand how frustrating it is to be locked out of your account, especially when you are paying for the subcription.
Before we proceed, may I know if you are having the same issue with your Microsoft apps. And if whether you've tried to log in using InPrivate mode and clear the cache? Please let me know.
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. I'll help you as much as I can to get back to your account. However, for more information on your account, please contact Microsoft Support or Xbox support. They will have more tool to help you with the account or at least stop the subscription charges while working on it. Thank you for your understanding.