Hi @dj
I’m sorry you’re dealing with this. The unknown address appearing during sign-in strongly suggests that the Microsoft account connected to Minecraft may have been compromised and its sign-in alias changed.
Please start with Microsoft’s Sign-in Helper and enter the original email address or phone number associated with the account. It will guide you to the appropriate recovery option and may offer the chance to speak with an account-support agent.
If you are directed to the recovery form, complete it from a device and location previously used with the account. Include any old passwords, previous aliases, Xbox gamertag, Minecraft purchase details, and other historical account information you can accurately provide. Use a separate accessible email address for Microsoft’s reply.
Please do not enter the password or send a verification code to the unfamiliar address, and do not post receipts, email addresses, or order numbers publicly. Unfortunately, community members and forum moderators cannot access the account, and support must verify ownership through the official recovery process.
Thank you for your understanding and time