CPA does not apply at Clicks

So I made a purchase at Clicks ****arney, of a Nido 1.8kg milk which was labeled R219 on the shelf. I got to the to till and the price was R229. I asked the till operator why was there a price difference and he went to check on the shelf and noticed the price difference. He called his manager Lucky to refund me the R10 difference. I asked the manager what the CPA says regarding incorrect pricing as it’s misrepresentation the consumer is supposed to get the product for free. The manager told me that there’s no CPA rule like that and it doesn’t apply at Clicks. Doesn’t CPA apply to all retailers???