********** transactions banks can’t manage to assist with

On the 25th of May 2019 ! I made a purchase at a store called KitKat at Pretoria West. Fast forward the 29th the payment transaction occurs and reflects on at my bank. The following day same transaction of same amounts goes through again. Same happens on the 30th,31st , 1st and the 3rd ! I went to the bank and I was told they can’t assist me because I made a purchase with the store so it seem like an agreement between me and the store so I have to go to the store! So my problem with the bank is why is it that they can trace overdrawn amounts from our accounts yet can manage to deal with ********** transactions! I know with this I will be charged in case the store decides to refund but where is the security we need from the bank!