bad attitude

I went to pick n pay on a Sunday afternoon. I was standing on the queue waiting For the machine to call me to the next available till like im use to, only to find out that the cashier called silindile was saying next and I didn't hear her as I was waiting for the machine to call the till number, when I left up my head she was saying next with a bad look as if I did something wrong.. when I got to the till I approached her and asked why did she call me in such a manner, she started to be loud saying \kudala ngithi next and awungizwa"meaning shes been calling next and I didnt hear.. I was stunned because of the attitude she was giving me then I said okay can I move and be served with someone else then she called her team leader or supervisor telling her that I have a problem"