Refusing to fix defective product

I bought two Twisp Aero's at the kiosk in the Garden route mall around three months ago since that time one has worked perfectly the entire time while the other one has not worked more than a week in those three months. The button that control the coil does not function at all, the mouth piece does not fit and liquid leaks all over the place. Basically I have not been able to use it at all for more than a week since I got it. I live fifty kilometers away and have taken it back to that kiosk six times now at great personal inconvenience but still no luck. The people at the kiosk is off zero help trying to blame me for the device not working and when he did take a look at it the only tool he used was a paper clip. I payed a thousand rand per device and they basically refuse to rectify their faulty device. Not only is this extremely poor customer service it is also contravening the CPA.