Account name is not mine but email address is

Take two parallel actions: secure the email/Microsoft account and stop/cancel the unauthorized Xbox purchase.

1. Check whether the email is a Microsoft account

• Go to https://account.microsoft.com and enter the email address.
  • If a password prompt appears, the email is a Microsoft account and must be secured.
  • If the message says the account doesn’t exist, the Xbox profile may be using that email only as a contact; still proceed with card/bank protection.

2. Secure the Microsoft account that uses the email

• If able to sign in, immediately:
  • Change the password.
  • Review and update security info (phone, alternate email) from the Security info section.
  • Turn on two-step verification if available.
• If unable to sign in or suspect compromise, follow the hacked-account recovery guidance and use the account recovery form if needed.

3. Remove or change payment methods on the Microsoft account

• Sign in at https://account.microsoft.com/security (or the main account portal) and go to Payment options.
• Remove any payment method that should not be stored.
• After receiving a new card from the bank, add it only if needed.

4. Cancel the unauthorized Xbox subscription or purchase

• Sign in at https://account.microsoft.com/services with any Microsoft account that might be linked to the purchase.
• Under Services & subscriptions, look for Xbox Game Pass or other Xbox subscriptions:
  • If found and not recognized, select Manage, then turn off recurring billing and cancel the subscription.
• For one-time digital game purchases or if the subscription is on an unknown gamertag, contact Microsoft/Xbox billing support with transaction details to request cancellation/refund.

5. Protect the credit/debit card

• Immediately contact the bank or card issuer to:
  • Report the unauthorized Xbox/Microsoft charges.
  • Request a chargeback for transactions not made.
  • Block future charges from Microsoft/Xbox on that card if possible.
  • Cancel the card and issue a new one if recommended.

6. If there are two accounts with the same email address

• If seeing a “Which account do you want to use?” prompt (Work or school vs Personal), sign in to the correct Personal Microsoft account (the one that truly belongs to the email owner) to manage security, aliases, and payment methods.
• If needed, rename the personal Microsoft account (change primary alias) so it no longer conflicts with any work/school identity using the same email address.

7. If the email is only used as an alias on an unwanted Microsoft account

• Once signed in to the correct Microsoft account, go to Manage how you sign in to your account and:
  • Add a new alias (email) and make it primary.
  • Remove the problematic alias if it is attached to an account that should no longer use it.

These steps ensure the email-based Microsoft account is under proper control, payment methods are safe, and any unauthorized Xbox purchases are canceled or disputed.

References:

• How to check if your email address is a Microsoft account
• Change the email address or phone number for your Microsoft account
• Which account do you want to use?
• Add or remove an email alias in Outlook.com
• Help with "phone number is already used" in a Microsoft account
• My credit card is being used by an unknown person to buy Xbox pass. How do I cancel the monthly payment? - Microsoft Q&A
• How do I send an email to Microsoft about my account being hacked and taken over by <removed> ? - Microsoft Q&A