A couple of days ago, I bought an Xbox Microsoft points card from my local supermarket. It looked real and it had the 25 character code. When I tested this code its said, "This code is invalid. Please try again". I then tried it two more times and it still didn't work. On the reciept, it said "Card will be activated within 48 hours". 2 days later I try again and it still doesn't work. Can someone please give me advice on what to do?