Discount not received

I received an e-mail from Red Square advising that they are running a special offer for a limited period, whereby you can purchase two fragrances online and receive a 20 % discount. I placed the order on 6 August 2015 and noticed that I did not receive the discount, I IMMEDIATELY escalated the matter and asked for the order to be reversed I received an e-mail on 9 August 2015, stating that my order had already been dispatched, but hey have escalated the matter for my account to be refunded. To date (after numerous e-mails and telephone calls) I have not received a refunded and I have not had any feedback either.