Incorrectly priced items

I'm disappointed at totalsports Musgrave. I bought a pair of sneakers for my son before Christmas, on display the sneaker was R550 I made a payment using my card and when I got home and checked my messages the sneaker was actually R650 odd Rands. I didn't check in store because I was in a hurry it was a mistake on my part but I feel like you should do a better job of correctly pricing the items that are on display. If I saw in store I would have demanded it on the advertised price.