Defamation of Character

I was furious when my wife told me about the incident. She went to the PnP store in Nonesi Mall yesterday(11/09/15) just after 5pm.She mentioned as she was walking down one of the aisles,one of the employees called her a fatty in Xhosa. He then said something else which she didn't understand and then called her a fatty again.She chose to walk on because she didn't want our 7 year old daughter to see that she is furious.Our daughter then asked my wife why that man was calling her names but my wife just shrugged it off.She then logged a complaint with the PnP call center and was told that the pnp branch manager would call her and much to her surprise, the manager didn't bother calling.Patrick went to my wife's workplace to apologise but she will not accept the apology.He doesn't have the right to call her or any customer by defamatory names.He then further said he only did it cause she goes to that specific pnp everyday.The manager of that branch expects my wife to go to him. He also mentioned that he doesn't want the regional manager to find out.I wonder what else they hiding from the regional manager.Something needs to be done about this. Or i'll take the matter further.