Horrible service

My parents had checked in for flight number MN455 departure at 15:00. We got to the check in kiosk for bag drop and were told gates were closed and we have to change out flight. When we went to the customer service desk there was a lady that I saw arriving same time as me and she was in the same situation. What I don't understand is that Kulula has always taken bags, but this time they couldn’t? The most annoying thing is that the lady we arrived with threw a tantrum and said she is going to board with her bag and she did just that. She was allowed in with her bag. So if we all throw tantrums are we all gonna get the same treatment? Tumelo at customer service even made a call informing his colleagues that the lady is coming through. Im appalled with with this service.