Nitrex interview questions

Tragicomic company interviews! I spent two months on this company for interview processes. I got five interviews, finally, they wanted to make the last in-person interview at the facility. After a long waiting period, they arranged my flight and hotel bookings. Then, I got a shocking message 4 minutes later. The message said that there is bad news for me, that interviewer has canceled the meeting, and will go in a different direction!!!. Non-sense and I guess no one can tell any logical reason for this. It is impossible to understand that kind of behavior. They are unprofessional and disrespectful as an international company. It was just wasting time...