Absolutely rude cashier

Absolutely rude customer service from Loshnee Govendor at your branch in Chatsworth, I was standing in line to pay for a 12 pack of 1.5 litres of coke which I use the cigarette counter at other branches and the cashiers don't have a problem with however Loshnee started arguing with me even after I had waited in the line to pay and even though there was no customers behind me, she didn't want to assist me, which means she would effectively just be doing nothing instead of helping a customer who was in line.

Her excuse for helping a previous customer was that it was a refund, there are no signs saying that this till was only for refunds or anything saying I couldn't pay there.