Day light *******

I want to make management of Jabulani liquor store that some of their staff is ringing incorrect amounts on the cash register and give customers incorrect change as well. Sometime last year I went to buy liquor at the same store I was short of R2 on my change I realised that when I was home since then I was checking slip after every purchase. On Monday I went there to buy one can of hunters extreme which cost R12.49 and my change was suppose to be R7.50 I gave the cashier R20 but my slip showed that I gave her R12.49 and she gave me R7.00 change. I asked her why is she giving me incorrect change with an attitude she said it's a mistake I asked for a manager by the name of Thulile Mtungwa and related my story she also gave me an attitude and did not bother to apologise. Can someone attend to this matter as is getting out of hand you will loose customers because of *********** and and management.