Bad customer service

On the 30th of October i purchased a couple of things from you clear water branch . I hadto exchange 1 of the items with another and the item i ended up taking was less than the original item and i had to get cash back . Cashier Tumelo Machailo gave me a R100 that is torn and i only saw it when i wanted to purchase with it . No one wants to accept the money i am stuck with it . I believe ahe was aware because she folded the money.