Returned Item but Takealot keeps saying they don't have it!

I have used Takealot for many many years and have being having issue with a return. We got my wife a Garmin watch strap replacement but the size was incorrect. So we returned it for a different size. Then they replaced it with the same strap and was advised to reject the incorrect size and give the return item. This was all done with the driver and both items taken. But Takealot keep contacting for collection of an item that has been returned and sent back to the warehouse and still confirmed it's there! Its been 5 times now for the same item and we are done! We do not have the item as the driver took the return and the I cancelled the replacement so they have both items! This needs to be addressed and need the refund!!