Bad customer service

My name is mita...i went to dealz store at parkmeadow shopping center in bedfordview opposite eastage mall...i went there to buy vaseline lotion which the shelf was all priced R39.99 of all the items merchandised there..about 5 same prices..when i get to the till point it scanned R79...i was told maybe the customer placed it at the wrong place, of which the item belonged there...iam very disappointed and ****ed for the explanation I was given for the wrong shelf price....i was helped by the lady named GUGU