False advertising

I went to sheet street- Clearwater mall on the 6th of April 2021. I wanted to buy a picture frame and was disappointed when I got to the till as the pricing was wrong. Is this some form of false advertising inorder to rip customers off- if something is on sale does the price depreciate or increase? When I spoke to the store manager by the name of Winnie- she was very unhelpful. Instead they quickly rushed to erase the wrong pricing using a pen. One of the shop assistants Hlulwani suggested that I take the frame at R230 instead of the R80 that was "incorrectly priced" but the manger refused.