Triple payment for goods

Yesterday I was at your Randburg square store and I attempted to make a purchase with my card and your machine kept saying declined .We tried the card twice and I eventually paid cash. When I logged into my online banking this morning , both transactions went off my account so I paid R120 off my card and an additional R59.99 cash which makes a total of R180 for a R59.99 item. I have my slip as proof of cash payment and I have my bank statement clearly showing the Pep Randburg transaction twice. I urgently require my refund please of R120