False advertising on discounts to draw customers

Makro online advertised discounts for bulk purchases, which didn’t register at payment. I informed them immediately, and it’s now a month of chasing on calls, emails, experience surveys and nothing is happening. They keep promising to refund me the discount, to no avail. It’s disappointing that such a large retailer can behave in this manner, misleading customers on discounts that don’t exist and then not doing anything about when informed.