You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I would like to go to a event in Phoenix, so could you please book a ticket for me?

ASSISTANT: Sure, please tell me your location airport codes. Ok, may I know on what dates you need booking?

USER: My source and destination airport codes are EWR and PHX. I would like to go on 11/15 and return back on 11/17.

ASSISTANT: Ok, could I have your name please?

USER: Myself Steven Lewis.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: That's ok, thank you for checking.

ASSISTANT: My pleasure, have a nice day.