Unknown account linked to my current account

Recently learned that my account has two profiles linked together. However, the one linked account has a recovery email and phone number I don't recognize. While speaking with support I was told not to delete the secondary (unknown information) account,
but was not given a clearrationale for this. The support agent informed me that account in which I was not familiar with was my original acct from 12 years ago. Should I be concerned?

:)

 

Unknown profile linked to my account?

Each Microsoft Account will have one GamerTag associated to it. To check the enforcement history of that account, log in with your MS Account to enforcement.xbox.com

I would also take time to review the security settings and preferences here: https://account.microsoft.com/privacy That will also show recent activity of your account to possibly identify any suspicious or erroneous activity.

It is highly recommended you set up security proofs on your account. To set them up:

Navigate to the Settings hub on your console, select
Account, and scroll over to the Your Information panel. Now select Account Security, select Security Proofs and follow the prompts from there. You may need to put in your email and password to continue
with this step.

Ex. Set Up Email > enter the email to send the security code to and select Done > select Next or I Didn’t Get a Code > if you did receive a code, enter the code and select Done > Continue > Done!

You can also update your security info online at account.microsoft.com. For more information on security proofs, check out our support.xbox.com article “Add
and update the security info for your Microsoft Account”.

 

Unknown profile linked to my account?

There seems to be a profile that I have no control over that has managed to get linked with my account.

I got banned from xbox live for whatever reason, when I got on my pc to see what I was banned for I discovered that there was a second profile there, that I didn't know of. The account has 0 games and 0 playtime. Can this profile get my account details? I'm
worried somone might get to my credit card details or something. Will upload picture if someone tells me how.

Thanks