EY RPA Developer interview questions

Well i got a call from e&y .The interview was going on, but due to some personal reasons , I had to discontinue the interview. I told the reason , Interviewer told that's perfectly fine and he can contact me in evening or may be next morning. But i didn't get a call back from him. And when i asked the friend who referred me , She told that's very unprofessional to cancel the interview like that. Well i didn't hung up the call. I explained the reason why i have to go. Second thing is you should conduct any interview without having an email invitation with timing mentioned.