Bought gems and didn't get them

So, i bought a giftcard (£25) bought £14.99 worth of gems. Didn't get any, looked at support. "Contact Apple" i did and they said they cannot provide me with a refund in this situation and i have to contact the game developer to get my items i paid for. So, i did and i kept getting the same response "Contact apple as they handle in-app purchases" i've not reached any conclusion of getting my money back or getting my gems. In-game support closed my case and now i'm here with no gems and no money. What can i do?

Apple do not allow developers to see purchases so Apple are the only people who can help.

If u have the receipt of ur gem purchase send it to support telling them the issue