Double charged for single item

I ordered online on the 12th of February through my Edgars account an OTP to approve payment was sent to my cellphone and the money was deducted off my account. On the 14th I got a message that it's ready for pick up.. I also checked on my account only to find i am now on a minus credit available.. When I called the customer care line they say I was charged again on the 14th for the transaction hence the minus credit available. Please rectify this because when I bought the item I had R 1334 and bought an item for R 964 and now I'm on a minus R 1553.