Price on shelf not corresponding with till slip

on the 24/08/2015 i went to Shoprite to buy Nivea Facial Scrub, on the shelf it was R36.99 and on the till slip was R49.99. I didn't see a till slip while i was still on the shop I only saw when I arrived at home . I came back on the 26/08/2015 and that price of R36.99 was still there. I called one of the Shoprite Senior to show the price i saw on the shelf and he show me the lady (controller at the store ) to help me but that lady was unhelpful she said to me the price is R136.99. I said lets go to the shelf i will show you what i am talking about but she refused and said the manager is saying no. I went to the manager to ask her what she is really saying cause the price you see is the price you pay. it took me 30min to resolved the matter cause they where refusing to give me with the price i saw. Their service was very poor as i was not alone complaining at that moment. I told them i wanted my R13.00 difference and if not i will show that price to CPA that's where after seeing me taking photos for that ,then they decided to give me my R13.00