Problems with Refund

I have been struggling to get a refund from this business. The day of the purchase the card machine went offline and the manager requested that I pay cash if I can, which I did. He would then check their records and phone me if the transaction did go trough and arrange a refund. This was 26 September. I have heard nothing from them since then. I phoned the store to follow this up with the manager but he was unavailable so one of the store clerks offered to help. I emailed all the proof of payments to him. He has now informed me that he has to verify with their head office that the payment did actually go through and that it reflects in their account (?) and would then get back to me. I have now phoned numerous times and every time I get the answer that the system is offline (it has been off for more than 2 days now) I want my refund, I cannot understand how this could be such an issue ?