Woolworths Fail To Keep To Their Shelf Prices

Purchased 2 X yogurt advertised on the shelf less 20% if one purchases 2 . The discount information is not loaded to the till which I believe is done on purpose as it's happening too often to be a mistake. Unless you check your till which most people don't ,you are unaware that you didn't get the discount. Sent several emails to their complaints department over the last few weeks but they are not following up and sending me refund voucher. Beware purchasing from Woolworths food and check your till slips before you leave the store as sadly they are acting *****ulently.