Deactivated gift card

Hi, I bought 2 cards from Tesco for my 2 daughters. When I tried entering the code on the first it said the card was not active and to contact the merchant. The second card it says the card is deactivated. I went back to tesco, for some reason they had not
activated the first and on the receipt the purchase was cancelled so I paid and they activated the card. It then worked. But they would not refund or help with the deactivated card, they said it was a microsoft issue.

To be clear, the second card was activated at the time of purchase as I have the activation receipt. When a card has been used already the message received is 'this card has already been redeemed'. We did not get this message so the card has definately
not been redeemed. Tesco did activate the card and their terms and conditions state when a card has been activated no refund or returns can be requested. I have asked Microsoft but they insist it is Tesco's issues and they sent me an email saying it is their
issue. I went back to tesco a second time and they said sorry but no, this is Microsoft's issue you need to contact them. There is obviously something wrong with the code but neither Microsoft or Tesco are taking responsibility for this. After hours of trying
to get through to Microsoft and 2 heated discussions in tesco, where does this leave me. Somebody needs to refund me then they can take the code that doesn't work and resolve this themselves as I am fed up of being a middle man just relating messages back
and forth. Customer support for both companies is shocking. Any advise from anybody would be great.

:)