It wont let me play the game even through i paid for it

I pay for the game and it doesnt give me an email to put in. after i pay for it i install and it asks me  to put in a microsoft email i do and then it asks for me to put in a gamer tag and goesnt let me put in one i put before. i get in and it says play demo when i know full well that i played for it. i even open up the game and it still says play demo. 

I will happily send screenshot for this situation.