Clicks promotions are a lie

I am a very unpleasant customer,on the clicks app is 1litre Organics of which the app says you buy 2 for 66.99,I didn't get that price on the app so I went instore for it and I also didn't get the price,your customer care consultant by the name of Sharleen who was assisting me said that is an error on the app and IT would correct it and there is nothing she would do for me,I must just pay the price on the app,I know this is incorrect because the customer must get the stock at the price they see on the shelf or app or catalogue,can you please come back to me as I still want the 2 products for 66.99 as I saw them on the app which I will attach to this email.Pleas also make sure the biscuits are correct at 50% off as I asked the store to keep aside for me.