Unsatisfactory service

Bought Hisense sound bar 2.1 but is not giving me the functions I want. Upon returning it to exchange for something else I’m told to pay handling fee cos the bar has hand marks. I over heard the customer service lady speaking in Afirikaans that the person that helped us will loose the commission. I mean I was not asking for refund but to exchange. I called the manager who told me that there is nothing he can do as the sound bar o brought back has marks. Store manager Danie van vuuren