Not refunding double transaction

I purchased an item for R1550.00 on 2 October 2015, with my credit card on budget, from Safari and Outdoor, Lynbridge Mall, Pretoria. <br> Both card machines were giving hassles. I gave up and asked the store to keep the item, so that I can visit my bank and double check my pin.<br> I returned two days later and advised the store that there was nothing wrong with my card but I had reset my pin anyway. We tried again and still had problems with the card machines. Eventually the transaction went through. <br> <br> In November, I noticed on my bank statement that two instalments were being debited. I contacted the store and started a process of enquiry, emailing them my till slip and proof of double instalments being deducted from my credit card. Therefore, the transaction must have gone through twice and I am paying for two items, in effect. I asked for a refund.<br> <br> To date, I have had only excuses and no refund. Management at the store has not contacted me even once. I received an email last week from an employee at the store, with a forwarded email from their bank who claims the double purchase was reversed. No proof was attached. I checked with my bank who confirmed there never was a reversal.