Kilimanjaro tiles wrongly

We have baught tiles from this outlet. The sales person showed is the glazed and non slip tiles. After 1 month of mails and calls, tests was done and the slip tiles was given for the stoep, and the non slip for our house. They want to come and fix the stoep. The test showed the problem. Sorry you baught the tiles from the display. The sales person took these tiles from the back and showed us. He assured us that it is slip and non slip. We got a mail from a very arrogant manager, which is not acceptable at all. Now all the blame is on the customer. I want Mr Lance Foxcroft to contact us. We will take this further. We were even told by another manager that if we use a mop on the non slip tiles, it would not last long, which is the case.