BAD CUSTOMER SERVICE

I was purchasing goods in discounts foods next to MTN rank JHb. I swiped and the tillpoint disconnected and we tried again and it disconneced . I decided to check my bank account and found out that the transactions were debited on my account and they refused to give me goods and my refund. The guy(not sure if he the manager) said the bank will reverse the transactions within 24 hrs but they were not reversed. I called my bank and they said they cant assist me without the decline slip . When I went back to the merchant for a refund they said they dont have a record of my purchase even after providing them with my bank statement. Iam really not happy with the service I got from Discount foods,my bank can reverse the payments but there is a fee that will be charged . I want my money back!