Refund policy and after service

I had an allergice reaction to Silki serum after i was seen to by their sermatologist and was advised what to buy, i immediately contacted them and advised of my break out and had bought products, they had advised to stop useing there products, i continued with the eye cream as that did not give me any reaction. However i needed my refund and was told 7-10 working days it is now two weeks later and no refund but jst empty promises via email that it has been done. I have requested proof of payment to be sent to me today and have not had a response from them. There after service sucks and refund policy is outdated. Not sure why they could not jst do the refund to my bank card like any other retailer does