***** false advertising

I've been shopping with Woolworths over the last 3 months, I registered a Woolworths card and also linked it with my discovery account. So I dedicated all my shopping with Woolworths. The first time I bought a special item (noodles, Asian veg, and sauce) discount x % I went back home and noticed that there was no discount. I went to another Woolworths shop and bought olive oil on special, again no discount on slip and item at normal price. I went to a third Woolworths, I bought 3 packs of dove soap, promotion 20% discount, again no discount. These cases I mention are the ones I randomly checked, I buy a lot of the promotional items and special and my guess is none is ever discounted. Now I checked it at the counter and every time it is issue/problem. This is *****, false advertising. I wonder if I am the only person experiencing this or if this is something Woolworths get away with because people don't follow this up.