false advertising

bought two x 6 hansa 500ml based on the adverti*****t in the shop that only states: " 12x500 ml Hansa for 130. I paid but was charged R89 a six pack cause apparently rhe R130 is for a pack 0f 12 x500ml. also they had no of the alleged 12 pack in stock. Shop attendants could not understand that when I explianed that it was false advertising cause no where does it states 12 pack for R130