Bad customer service at Eastgate mall Woolworths

Woolworths Eastgate mall I did not receive a great treatment I went for shopping I found this 2 Levi’s Jean on special the other one was R549 and the other one was R399 when I get to the payment point the prices changed I ask why ,the manager said she can not sell this Jean with this prices because it’s not them who putted this prices on the jeans the customers switched the prices of which i didn’t understand I was treated so unfairly