Trouble with prices at R55 cash crusaders

I went shopping at cash crusader at the R55 mall we saw locks at a good price of R29.90 we decided to purchase but we were refused to buy it at that price cause apparently what we saw was not the right price that was corresponding with the one on the system at first the manager Martin coetzee took some time to come see us and told us the rule of the price you see is the price you get doesnt apply to his store and that he reserved the right to take the deal or not and he was suspecting us of changing the prices so we suggested he must check the cameras if he wants to and he told us he was too busy to do it or help us