1 minute late for checking don_A|_t want to help

I want to complain and requesting a refund for my air ticket from Johannesburg to Durban. My ticket said that we need to check at the counter by 6.00am yesterday morning. i was standing in line and wen i got to the check in counter it was 6.01am and your staff refused to check me in on the flight. i told them that this was not acceptable and surly they can assist me as its only one minute. they still refused and told me to go to the help desk. i got to the help desk and told them what happened and they said i need to book a new flight and pay R925.00 so that I can go on the 7.00am flight. i didn't had time to argue as I needed to get to Durban for Business appointments and paid the new ticket. On my bank slip the transaction happened 6.03am. So from the time that i got to the checking desk to the help desk and paid for a new ticket it took me 2 minutes and im sure your useless staff could assisted me in getting on my original flight. when i got true the gates ii noticed that my original flight didn't even board as it was only 6.10 and there would have been more that enough time for me to get on the plain. My flight back from Durban to Johannesburg was delayed with a hour as well