Bad Service and Robbing of Customer

I went to put R50 petrol in at the Engen Garage by the airport this morning, and i told the petrol attendant to please put R50 in, after a while i thought to myself why its taking so long, next min i see she's putting in over R200 i told her STOP!! i told you R50 and then she went all viral on me and verbally abused me and saying that i said R300, i told her how the Flip does R50 sound like R300???? i told her to call the Manger and i explained what happened but he clearly took the petrol attendant side, he did not handle the problem probably and does not know how to speak to customers, the service is shocking their and i will never use that station ever again!!! i eventually had to pay what was put into my car which was R231.00. I recommend that know one uses that Station until those people know how to give Good Customer service and know how too speak to people probably, I'm sure know one wants a petrol attendant shouting at them so early in the Freaking Morning!