Gift voucher failure

Poor customer experience. I received a gift card as a gift. The card says that it can be redeemed online. When it didn't work at checkout, I contacted yuppiechef to find out what's wrong with the card. I was told it was a promotional voucher and I needed to come in store to reveal how much it was. When I clarified that it was not a promotional voucher I was told that I needed to provide them with the name, surname and email of the purchaser. I'm the recipient of a gift, why is it suddenly my problem to prove it? It clearly looks like its just something wrong on their system but now I have to go to some strange lengths to get additional details?