SpaceX Firmware Engineer interview questions

A SpaceX recruiter called contacted me on Linkedin with a job opening in avionics department. An initial phone screen was scheduled but recruiter never called me back. I left a message. Few days later he responded back asking for time re-schedule phone screening again. Another day later he cancelled the interview saying that firmware position is no longer available. Seemed to me he got upset I did not respond within a hour of his email. He was not being professional. Was disappointed at the end.