RUDE Cashier

On Saturday, the 1st of July I went to Clicks in Plumstead 3 Arts. I needed sanitary towels for my daughter. I bought Kotex which was marked as R20.99 on the shelf. When I got to the cashier -- it scanned at 23.99. This is NOT the first time that this has happened and it's downright annoying!!!! I politely informed that Cashier - named Shireen that the price needed to be updated and she just stared at me blankly without acknowledging me at all. So I repeated myself and asked if she had been listening and she gave me a filthy look - still not answering -- I then said to her, "Don't give me that look!! I am the Customer here" and she continued staring at me. I was utterly disgusted!! Someone like that should NOT be allowed to interact with PEOPLE let alone Customers