Bad service

My name is Nompumelelo Twala.I want to review the bad service I received from Game Retailer to trade route mall in Lenasia from a lady called Lesego Lebogo last week Saturday on the 04/08/2018.I went there to return a kettle that was faulty ,when I went to customer service the lady was very nice ,she checked it and gave me a slip to go and take another one and go to the till.When I got the floor they had the brand but not the same style,I took it and went to the till,the cashier called Lesego to come help her but when she got there she was just angry and said they don't have this kettle anymore so I must add some money and take the one they have at the store.I requested her to check if other's stores have it ,she went to make a call to check ,she come back 20min later she said they don't have it anymore.I said I don't have money to add on ,she said there is nothing she can do about that.I requested to be refunded my money ,she said okay you can do that am coming she left me standing there for another 20min until I decided to go to another manager who said I can go to the refund at the till point,so I don't understand why didnt she tell me to go do the refund at the till.