cashier underline wrong time for as departure time

I was at Morgenster Centre at Mitchelle Plain, Cape Town on Wednesday (21/07/2015) to book a flight at Compu Ticket on British Airways from Cape Town to Port Elizabeth.<br> The Cashier that attended to me book the ticket for me. When she explained to me about the booking details, she underlined the Arrival time as my departure time which I did not notice that until I got to the airport and find out that the flight had left. <br> I went to British Airways count they gave me refund department phone number ***. I phoned refund department but they couldn't help me. And I phone Compu Ticket also no one is willing to help my out.<br> <br> The amount for ticket is R951.12 and I want them to refund me back because the fault is from the cashier who gave me wrong information about the flight time of departure.