Just based on what this sounds like, I believe I have an answer for you. If you are trying to put another profile on an already created profile (or Avatar), then saddly, we are out of luck. The system is set up for one account per email address. Sad, I know!
But, if you are just trying to add some gold time to your account, you can do that very easily right from your xbox!
From your home screen, we are going to choose Settings and then choose Account.
From Account Management, we want to go to the second page, "Your Memberships".
Under "Your Memberships", we want to choose Xbox Live Free. This is your Xbox live membership.
Then we are going to follow the on screen prompts for pruchasing Xbox Live Gold time!
If this doesn't solve your issue today, can you give us a little more information about the issue. Are you trying to just change the email address you use to sign in? Or are you trying to merge two accounts together?
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