Incompetence of a company called Buyinstor

I am disappointed with the company called Buyinstor. On 31 March 2025 I placed an order for a hair product namely Goldwell Kerasilk Control Smoothing Fluid. The order number is 6012. On 14 May 2025 one of Buyinstor's employees sent me an email explaining that the product was out of stock and asked for my banking details to refund the amount of R1420.80. I immediately sent her my banking details via email. To date I have not received my refund. I have sent them several emails in this regard. I sent a WhatsApp to them on the number I found on their website. To date they have not read my WhatsApp and there are no numbers on their website to contact them telephonically. Could you please help me regarding this issue.