I have an old account by the name of Twitch M8st3r47, the original email has been deleted...

They must have added that email to the account and deleted my original email because whenever I attempt to sign into my old account with my original email, I get the notice that an account with that email does not exist.

Another thing to think about is the age, every few years they go and delete old account to free up gamertag names. I know it has to be a really old account to get deleted but the age was not stated in the original post.

Hello, first it's a pleasure to be able to help you today.

My name is welcome to the community.

Hello Weessykes, as this is an email from Gmai you will have to contact Google support or check if there is a possibility that the account has been deleted due to inactivity.

If you tried to enter that email in the Gmail where you originally created the account and couldn't, it may have been deleted.

https://support.google.com/a/answer/38173?hl=en

Good luck man, I've tried for a few years and made multiple calls trying to get back my original gamertag. they keep asking for the credit card that I originally paid for xbox live with back on the original xbox. That card no longer exists, I can give them
my old address, my old phone number, but not the email. I have passed virtually all tests, they even say that it is in my name(so I know that no one else is using the account, and it hasn't been logged into for over 6 years), but can't help me further...isn't
that a little odd? Anyways...yeah, same situation, but I'm trying to get my old gamertag even if meant buying it, but they act like I'm asking for something completely unreasonable, I'm trying to get access to an account that has been unused for half a decade...I
would have expected it to have been deleted by now and the name to be up for grabs at this point, but its not.?

You have to change your gamertag, and sadly you do have to buy it, unless its like on your old account and you have a new one, you'll have to stick with the name with some numbers. If you want to have the original name, contact microsoft into maybe deleting
your old account so you can have the name, hope this helps! (Be sure to have to old accounts info before trying to delete)