I'm not sure what's wrong but when I type the GT you provided on the Xbox website it comes up with your profile.
Well have you gone to the email of the account? Sometimes Xbox just needs you to update information about the account. Also you could try to clear system cache on your memory unit. That helped me then i redownloaded it
My Xbox account exists.. but it doesn't have an email attached to it. I am unable to re-download it.. my email doesn't register on the server.
I know what my email is.. I've been using it for 3 years, now. It just majorly failed and dissappeared?