GIFT CARDS NEVER USED BUT ZERO BALANCE

I received 2 Outdoor Warehouse gift cards from 2 different people and have never used the cards . When I went to Outdoor Warehouse Stoneridge they said that both cards have a zero balance - I know the gift cards haven't been used because they have been in my wallet the whole time . Absolutely dismissive attitude from the staff , they just said sorry the system says the balance is zero there is nothing they can do , they cannot even provide me with a transaction history to prove that the cards were used !