Unhappy with Capitecs Service

On the 24th December i purchased some things at a store called AHK motor-spares, the amount was R670 swiped my card the first time and it declined on the stores side, however this transaction went off my bank account, they told me to swipe again it went through. i then checked my bank statement and noticed the transaction went off twice even though it declined on there side the first side. They then told me its a issue with my bank. I called the call centre who told me to send proof of the declined slip and approved slip, she also then said if i went to the bank the refund would reflect immediately. So i Went to the bank and they advised me they will be able to refund me however they will charge a fee of R70 and it would take 7-14daysi said fine no problem, the teller also advised me someone from Capitec will call me back asking security questions just to verify this refund, no call whatsoever , i have no idea what is happening to my refund. the reference number i received for my query was 7*** can someone please tell me whats going on!! not impressed at all