Disrepected and humilation by manager and cashier

Gae menlyn park is on another level of being disrespectful.i went ther yersterdae before they close,i wanted to buy pots ,my told me about the brand called mainstay.so when we get ther the shelf label was saying R299 and when i shoud pay the pots are R479?i told the cashier cynthia that the shelf label is written R299 n she said its not her problem.i asked her to call her supervisor n the lady said pricing was wrong.i asked for the manager and manager told me that hes not reliable for the shelf labels thats been changed with black people customers.i was very crossed to the extended that i stood there until 21:00pm.both cashier and the manager gave me a very stunked services.the manager said he cannot authorise it for me cause he is not realible?until he did authorise it.i swear i wouldnot never sat my foot there and i will take it to action.being so dispected is totally an issue?