refund declined

I have bought USB hub from takealot.com in December 2019. I've the payment and they deliver the item. The hub is not supperted by Windows 10 because the itme was designed for Windows 7. Windows 10 don't recognise this product. I have ask for a replacement which they did,but they replace it with exactly the thing. This time I request a refund. I supp**** everything they need for the refund. Now they say that refund was declined and they will give credit on my on account. I don't want that because I'm prepared to do business with them again.