Trying to rob me

Hi, i need to know where can i go to report a rude staff member I went to Pick n Pay Maponya mall to buy groceries upon paying ask the cashier to add airtime, after the transaction, i asked where the airtime was and she said she did put it in she forgot with an attitude, So before going out i doubled checked my slip and only to find out that I payed for the airtime, so i went back and another lady working there tried to assist me, of which i told her that I'm running late already as it is so if it is going to take long she must give me my money back, so after 15 min of me waiting there i went back to the cashier and asked if she could just give me my money back her reply was "aww your money back really" while rolling her eyes ...does the lady know what customer service is? Can i get assistance on this?