Hi there can any body please help

You should be able to change it from the settings menu on your Xbox. It would be under" Account" and I believe account security. From here, you can select Microsoft account and change the account that is linked to your gamertag. If this does not work, and
there are no other correct solutions in this thread, contact xbox support at the link below:

https://beta.support.xbox.com/

Hey there DanielBowen2,

Thanks for reaching out to the Forums for clarity on working with an account situation like this. I can totally see how this could seem like an urgent issue that you would like to get dealt with in a timely manner. The closest thing to any kind of transfer
of a Microsoft account would be to change the sign in email for it as outlined in Change the email address
or phone number for your Microsoft account.

After you make the change (which may take time to take effect), it would be best for you to remove your ex's old information.

Hope this helps.

Thanks for reading!

So if they approve it will it be under my account and have nothing to do with their account

But if I create a new account wouldn't the original user account still be operable for example if the old user uses a new password would it affect my new account

You can just create a new account . Make a new user login to your old account as a new user. Set as home Xbox in settings and good to go . It's easy fast way to do it .