Bad Service called 'Nunuza' by the employee

I went to the store to buy staff for my brothers new born baby, I have never been ofended like these by the employee working for Ackermans, 'Nokuthula ' ' I am greeting her 'hi sister can you please help me ' and her reply was 'yes nunuza '. I lost it right there never even knew what to say to her. I asked her why you calling me 'nunuza' and do you know me ,how dare you do that to me as a customer ,she should have asked for my name if she felt like . She continued arguing with me claiming that she dont know if I am kid or an adult and what my age has to do with me asking for help !I was so surprised to meet these lady 'Nokuthula' in forest hill city , I am not sure if, is these how you teach employees , professionalism to call customers with names like 'nunuza' I am very angry to the service we got in these store , that is why I dont even want to open an account with Ackermans , I am actually hurt and felt harrased. Hope you Ackermans teach your employees how to be professional...

Thanks Donald