Dissapointed with takealot.com delivery services.

I ordered 16mm spark plug socket but takealot delivered 21mm spark plug socket instead , I logged a return and clearly indicated on the return form that I want a replacement as I needed the tool to service my car but to my surprise, takealot opted to credit my account instead of replacing the incorrectly delivered item. This to me is poor service as I will have to pay for delivery should I make a new order from scratch for the right socket.