I bought a gift card and it doesn’t work

So I’m a Canadian and I was trying to gift my other Canadian friend as a present for Christmas as we are making a game and he redeemed it and it said error and I tried it and it says it’s already been redeemed I’ve looked everywhere for advice and couldn’t find anything I have the SDM receipt and the gift card and don’t know where my $15 dollars went I even have the notification I bought that stuff from the store and his account still hasn’t gotten the quest cash as both accounts are empty