Refund

I went to sheet street about two weeks ago, their card machines had a problem which led to them charging me twice, the sales lady advised that if the money isn’t refunded back to into my account I should return to them with my bank statement, on Tuesday the 15th I went back to the shop with my bank statement and I was told that head office is closed and my refund request will be done the following day, nothing was done so I called the shop yesterday the 21st I was told the manager Sipho will be in at 12 and someone will call me back , today I can’t get through to them .It is so frustrating because I have been given the run around as if I was the one at fault, I need my refund ASAP and can someone from the shop get back to me with an update