Online false advertising

The woolworths app is always false advertising, this is the second time that I tried purchasing a branded product whilst apparently on sale,they provide us with these vouchers that doesn't work,I've tried multiple times to make the purchase but I guess that the price is just to good to be true so the order refuses to go through,I have a screenshot of the item and the price that I was supposed to pay from the online app,I've complained twice now on the app and they don't bother responding.