Bad attitude just for a cash back

On the 5th August I visited checkers Musina to grab a few things while there I remembered I needed cash so I asked the lady(Eniya Makhubela) assisting me for a cash back of R100. To this she responded she doesn’t have money or unless I want R50 because she had done some cash which I don’t know what that is. So I told but I need R100 could she get it for me elsewhere, so she calls this other man(Dakalo Kwinda) to come. He comes now they discussing if she doesn't have R100 she again tells him no she has no money. He then presses on the till and after a while I am told to swipe my card then the till opens and I am given 5 R20 notes. So I ask the lady why didn’t want to do a cash back for she keeps quiet and looks away, I ask her is she not aware checker offers this service then she just ignored then I ask fir named since she was wearing a jacket and the badge was not clear she points to the slip and says you will find it on the slip whilst rolling hers eyes and giving me attitude. Cash back is a service that we as customers are offered by you and we do not need to beg for your cashier to give us our money like I am asking for a loan and the attitude needs to be adjusted as its part of her job and I am not asking for anything special or for her to even go the extra mile.