Still battling to get a refund of my November 2020 payment.

I ordered an electronic part for R847.00 in November 2020. Not once did PC Link Computers update me on shipping and delivery progress. In January 2021 I finally got a note to say that the supplier had cancelled the order. I then asked for a refund on 26 January and wrote again on 10 February and monthly to 21 June to enquire as what progress was being made. Garth Botha and Dehan Willaims keep replying that they would follow up with accounts. I have heard nothing since. To do a sale they are extremely efficient and once payment has been made then they don't seem to care. I am not sure what to do to get a refund of my November 2020 payment.