Clearpath Technology Software Test Engineer interview questions

I was told its a scheduled interview on Feb 13th 2016 but it turned out to be walkin with various platforms, android, testing, dot net, NC etc. After waiting for 4 hours, they called me for my turn and that interviewer asked basic questions and finished the interview in 5 mins. After repeatedly trying to reach the HR, they kept saying they did not get feedback and finally they reply yesterday I am rejected....without valid reason.