Thomson Reuters Sr. Software Engineer interview questions

I have attend interview through scheduled walk in. There are 2 rounds both are technical and once after clearing both of them I had salary discussion and everything via phone. I have cleared first round and they said me to wait for the second round. After waiting for 2 hours they said that they will conduct 2 round on another day, I didn't understand if they want to schedule it on another day why they requested me to wait.

The interview process is a 3 round process 1.Ttwo telephonic 2.Two Face to face 3.one HR discussion. I was asked with basic questions in telephone first round, slowly the intensity of the interview will get increased as you go to the next rounds