Made me double pay and yet still no refund...

I went with my girlfriend to Woolworths at Jean Crossing Centurion on Saturday the 5th of March. We bought some flowers and coffee beans as a present for someone along with some drinks. When we got at the till I swiped my StandardBank cheque card and it was declined. I swiped it again and the result was still declined. I asked my girlfriend to try with her FNB card and the transaction went through. She paid for the purchase. About 20 minutes after when we were on the Highway on our way to Limpopo the two transactions went through on my account. 5 minutes after that one transaction was reversed and the other wasn't. Now we have paid double the amount. My girlfriend paid and so did I. I went back on Sunday the 6th of March and they said I must go to the bank to get statements. This was not my fault and as being a Software Engineer I have no time to go to the bank. They promised to call me today and still nothing. This is not my problem but it is MY money and I want it back asap. I hope I can get through to somebody on this. It is a pity that I must go this far just to get something that belongs to me. Woolworths was always one store with good service...