ACSA complaint at the King Phalo airport in East London

I'm reeling from the horrible treatment I have experienced on a flight I was on time for but was denied access because I was told my bag is too big. Apon review with a FLYSAFAIR personal my bag was measured in the dimensions box and is the correct size. There is nothing wrong with my bag size. I have been forced to book a standby ticket or suffer even more loses including my return ticket from JHB to EL. When I ask why the security let me through to the waiting area I was told they are just security they aren't part of ACSA. This is ridiculous because it would have saved me the stress. Also when I went to luggage check in to measure the weight of my bag the personal there said this is hand luggage it does not need to be checked in. I was told that footage would be reviewed but this doesn't excuse the treatment and distress I was put through over something that could've have been resolved if they actually measured my bag instead of eyeballing it.