Wrong Pricing on Shelf

I was just in to buy a pregnancy test, which was advertised for under R50. but when I got to the till it was R53.25. I know this sounds petty but I worked in retail for over 10 years and know the consumer act law well enough. also when I mentioned it to the attendant she just came back and said no sir it's the right price. NOT happy at all with conduct of transaction and therefor I will advise all my colleagues at work to rather support another branch