Wrong adverti*****t

Yesterday me and my sister went to the store to buy camp chairs, when we get upstairs we saw two different chairs with different prices, we saw this colourful ones priced R199 we took them and go to a cashier to pay, to our surprise when we check till slip because we were using speedpoint we saw different price R399 then we asked another lady about it she advised us to go upstairs and ask a person responsible for that department, we went and spoke to a guy called Quinton he explained that only orange chairs where 199 and advised us to either take the stronger ones as they where R399 we took them to refunds n he explained a lady what happened, they gave us refund in a form of voucher when we about to pay for these other chairs price was different from the one on the display and that's where they called Mr Ntuli and he said according to MAC he can't give us chairs with price we saw he rather calculate a price for us, according to me there must be a law to punish stores with different prices on display as it is a wrong advertising