Boss Doesn't Have Time?

Was just hired to report directly to a Big Shot at work. He was formerly my customer as I was a consultant. We worked together very well. Now I must stand up an entire element at work and he promised a close working relationship as before yet for 7 weeks now he has cancelled all of our meetings and does not have time to talk when I go to his office. It is starting to hinder progress. Why is he doing this and what should I do. (Mind you, I will not do anything disrepectful or rude ... want tactful answers only) Thanks.