Bad costumer service

when i realised that my make-up color was not on the shelve i decided to open the drawers at the bottom to check there, as i was closing the drawer Dudu Masondo came and said i am not suppose to open the drawer, i apologised and told her that i was not aware that i was not suppose to do that and asked her if there is anyone else who can assist me since i saw that she was busy assisting another customer, Dudu said to me AS YOU CAN SEE I AM THE ONLY ONE HERE, i think this reply was rude,so i corrected her, i thought she was gonna call 1 of her colleagues to assist since it was a holiday and the shop was not that busy, but no Dudu started telling me that i must admit to my mistake i have no business opening the drawers shouting at me in front of other customers which is so unprofessional and had a bad attitude, at that point the supervisor came to authorise something for her she saw what was happening but did not even intervene. I got very frustrated i left got to the door turned back to get her name. DUDU Masondo was still going on and on. Dudu Masondo needs customer care etiquette she lacks that she is not suppose to be arguing with customers.