Don't follow an ACSA staff member to another que

I arrived at OR at 6:30 for my flight at 7:30. I was flying with FlySafair and for some reason an ACSA staff member took a whole bunch of us to an ACSA check in. She said there is a shorter que. when i eventually go to the front i was told my bag is too big and i asked why was i brought to their que as she saw my bag was a check in bag. I missed my flight because of this. My colleagues had the same experience of being moved to different ques.