HELP? URGENT.! ADVISE.!

What to do about this.? I went to the Dollar General JAN 1, 2019 and bought 2 xbox live cards. The first was a $9.99 1 month gold membership card. The second was a $50 xbox gift card. As the attendant rung them up he kept saying they wouldn't activate and
had problems from them. Well he finally got it resolved. After a couple days JAN 3, 2019 I used the cards and it said this card in not yet active, please contact your retailer to activate this card. I went to my retailer and the same guy that sold them to
me was very rudee. Told me they should work fine, that they was activated at the time of purchase. And to make matters worse i can't find my receipt. But they can run the card through their system and see it was purchased. Plus the guy even remembered me coming
and buying them.!! So now I'm out $70..unless i can find some way to resolve this..! PLEASE,.! ANY AND ALL THAT CAN HELP WOULD BE SO GREATLY APPRECIATED..! THANK YOU ALL SO MUCH FOR ALL HELP AND INFO..!!!

:)