Lying sales people de*****ed elderly lady

My elderly mother in law bought a laptop from Edenvale Makro and was told by the sales staff at the till that she had to buy a Microsoft Office licence or else her laptop wouldn't work. When she got home we told her she does not need the licence. We went back to the branch today and they refused to let us return the unused licence. So not only was my mother in law **** to and de*****ed by lying sales staff trying to make more commission the store manger now refuses to help. Absolutely disgusting. I will never shop at makro again if this is how customers are **** to and de*****ed