Disappointed customer

I requested cash back from Pick n Pay Musgrave. Requested amount was debited from my account but cashier said transaction was unsuccessful. She then told me it could be a system error my bank will credit me. After a while I called the bank & they requested decline slip from Pick n Pay. Cashier Thembi then suggested that I look for it in the trash can as she had paying customers waiting for her services. I was shocked by that statement & asked her to look for it. She was casually chatting to her ***orkers and not bothered while I was waiting for her to find the slip.