Complaint about a worker

Today Inwas at Dis-Chem Sprins mall. The lady Zinginwe helped me and I've asked her what is all the tablets for and then not to give me a specific one. I also asked for meds that was there for collection for my mother. Whrn I got homr I've sorted the meds and saw that she did gave me the ones I did not want and the meds for my mother was nit my mothers meds. I went back and told her about it. Shr told me that I didn't told her and she was very rude to me. I've asked her what about my mothers meds that's not hers. She then didn't want to give me the money at first and wanted ro give me a voucher. I've asked her please I cant take a voucher but she keep on telling me I cxan use ot whenever I want. She was not happy to give me the cash. She wrote in her book that the customer no longer wants the meds and I told her thats not true I did not tell her. So I'm a ****. But at the cashier she said she's sorry. I was really unhappy, I'm not staying nearby the mall I'm far from it.