Hi dylan,
Welcome to Microsoft Q&A forum.
To narrow this down, please share the details below:
- What is the current primary alias shown (does it end ******@xboxlivefamily.com)?
- On Manage how you sign in, what is the exact message you see when trying to set the new alias as primary (e.g., “policies prevent…” / “Make primary” missing)?
- The new email you added:
- Is it Verified already?
- Is it a personal email (Gmail/Yahoo/Outlook.com) or a work/school email? (Work/school can be blocked.)
- Is this account still under a Microsoft Family / child setup? If yes, is the Organizer account accessible? (Some changes may require the Organizer.)
Once these details are available, the next steps can be confirmed.
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