Misleading advertising and unwilling to refund

I bought and paid for an item from their online store for about R17,000. The following day they called to say that the item was advertised at an incorrect price and the new price was R24,999. I asked for a refund that they promised me would be processed within the next "couple of days". I had to badger them every few days (by telephone and email) for about three weeks, each time receiving promises that the refund would be paid "later today or at worst tomorrow". I eventually threatened to write bad reviews in the media ... after which the refund was paid within 3 days.