How can I return 50% fund to a buyer?

How can I return 50% fund to a buyer?

Hello,

I promise 50% refund if the buyer is not satisfied. I refunded once previously also and it was very easy but now it looks difficult. There is no link to refund. Buyer is telling me to buy the gift cards in this link

https://www.seoclerk.com/buygiftcard

Is there any other way to refund? Whatever payment we get from buyers, 20% of that goes to SEOClerks and now in refunding if I will be buying gift card then that 20% will also go from my account. Please suggest what to do. Please help.

Thank You