Rudeness behavior

I have experience rude behavior, shouting n insults from one of the Passanger Service Agent by the name of LUCIANO KOETTEAN at Johannesburg International Airport when we went to drop off bags, we query about paying twice for Luggage. Instead of explaining to us why we have to pay twice, he shouted, screaming at us and he didn't even want to help us. His colleague had to take us to another agent as he refused to assist us, even when we were at the other till, he carried on discussing us.