some reason years ago i made and add some xbox account and now cant remember the details. cant do cross save until i work out the details and cant remove it because again dont know the details.
You'll need to contact Xbox support to recover your account. Bungie cannot manually unlink accounts from users' profiles. If you are unsuccessful in recovering the account, you'll need to create a new Bungie.net profile and link your current account(s) in there. Note that creating a new profile and abandoning the old will result in you losing any purchased/earned special emblems as they are tied to the Bungie profile.