False advertising

I saw a catalogue a catalogue for this previous long weekend where products were up to 50% off.i went to the store and bought a 2 seater couch and bought one which was 6999 and on Monday 24th I heard an ad over the radio which said the prices will drop 15% further on heritage day.i phone a store consultant and she told me it's true, which meant I would get the couch at 15% lesser. But when I got there I was told the prices were changed back to normal by head office. There was another couch I wanted to buy which was 3999 but I couldn't even buy it as the prices were back to normal. I believe this was false advertising by the store. Kindly assist