Ripped of because there online chexk in does not work

If I could give zero stars I would. FlySafair are ripping people off. Today I checked in online only to get to the gate and being told that I did not check in (eventually about 15 other people with the same issue at the ticket counter). Then they made us all pay an additional R500 to be placed on the next flight. I seems that they are doing this on purpose just to charge an extra R500 for your flight. Stay away from FlySafair at all costs.