Misleading signage

Pop in to Woolworth's Menlyn to get my employees lunch. While going trough to the tellers picked up 2 tubs of cashews as signage was saying buy any 2 for 100. By the cashier discovered that it's not on sale apparently there is 400g and 500g. I insisted on the price but gentlemen in charge told me that I can't get it besides he said that anything on that shelf can be 100 rands. First he said save 100 rands. Basically he wasn't sure himself about promotion. Honestly very dissatisfied and disappointed. Will be taking this further as signage which was placed there is misleading. Regards Irina