Want my old name back

Hi, if you haven't already, I'd try using the Microsoft Lost Account Guide to try to recover the email address: https://support.xbox.com/my-account/microsoft-account/forgot-microsoft-account-solution

Note that the guide may direct you to contact Official Xbox Support if none of the presented solutions work for you. You can contact them at the following link: https://support.xbox.com/contact-us

Best of luck in recovering the account!

this may be helpful https://support.microsoft.com/en-us/help/17875/microsoft-account-recover

this haapedn to me let say i play fortnite yh and is say my paid name then when im in party it say my old name i want my money back

You'll want to contact support. As long as you can verify you are the owner of the account, they can get you the email. 1-800-4my-xbox if you're in the US/Canada or http://support.xbox.com/contact-us

There's no way to know exactly how inactive an account is. It's possible their signing into their account on other Microsoft services which would keep it open.