Refund not processed in 20 days and counting

Bought two "memory foam" pillows on the 16th of December. The pillows were not as advertised. quality was cheap and plastic and I arranged for a return via their courier. Packaged the items, handed it over to the courier on the 20th of December and followed up 3 days later. Initially no response was received after which I received a response thanking me for my patience 7 days later. Spoke to two different customer representatives and neither of them were able to locate my returned product nor responded to further prompts via email. No further information was received regarding my refund that still hasn't been paid.