Defective goods

I'm so disappointed with the workshipman on your smart shoes. On 23 November 2019 I bought this pair shoes at Ur Chris Hani branch and only wore these shoes for 2days , to my surprise today when I'm about to wear the left shoe is defective due to poor workshipman. I have misplaced the slip as my proof of purchase, in terms of NCA act 68 of 2008 section 16 ,unsafe or defective goods may be returned for a repair,replacement or receive a full refund. Please help I cannot afford R600 to go down the drain just for the fact that I misplaced the cash slip as proof of purchase , I believe CCTV are not there just catch ******* but as I remember the time I was the they can be used as a proof that indeed I purchased these shoes and other items at