Rude cashier

Boxer has the worst cashiers you can ever find in retail. This morning, I went to Boxer in Alex Plaza to get a few things, I made my purchase and asked the cashier for cash back for the amount of R20 which I needed urgently to pay in a taxi because I was going to work. The lady gave me my slip and not the money I had requested, I than tell her I asked for R20, and she does not even look at me she says I do not have it while serving another customer. I am pretty sure there is footage to prove that she had money in her till, a mere R20 and she gives an attitude for my money. I was at the store at 7:05am today and the cashier's name who gave me bad service is Zimkhitha Jama. I demand an apology from her. She needs proper training.