BAD, RUDE unmannered cashier

I visited the restaurant on the 13th of January 2016 with a friend to purchase the Mc flurry. My friend purchased the original Oreo Mc flurry for R18. When it was my chance to order I then spotted the limited addition Mc flurry flavors I then ordered that and at that moment my friend wanted to change her order and order the exactly the same one as mine. Ntebo the cashier said that she needed to pay for the top up which was going to cost more. My friend refused to pay the top up and asked the cashier to cancel the order and redo the order of the limited offer Mcflurry. My friend then gave her the R2 and the cashier literally through the Money on the counter and then turned her back on us and called the manager/ supervisor if she can redo the order. The supervisor authorized the cancellation. Upon her return to the till the cashier did not give us feedback if it can be done or not. While standing there she then starts serving another customer ignoring us flat. I then asked her what is going on, is she going to fulfill our request or not. And she rudely rep****\ they are busy preparing your order"rolling her eyes. I lost it and I asked for the manager and told her how we were treated"""