Very unprofessional HR. After giving positive feedback on the 1st interview and telling that she will be conducting a second one, i stop hearing from her. On top, there is no response for any phone calls or email.
Just a waste of time if they were not intending to hire anyone. Even if there is a change in the plan, the HR must convey the status to the candidates. But looks the HR people don't know the rules of the profession.