You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you at this moment?

USER: I am John Jackson. I am planning to book a ticket to attend a meeting at IAD. Can you please book a ticket from PHL?

ASSISTANT: Sure, I am happy to aid you in booking flight ticket. Can you please mention your preferable travel dates for booking flight ticket?

USER: I would like to travel on 06/24 and return back on 06/26.

ASSISTANT: Just give me a moment, I will check flight availability in this route.

USER: Sure.

ASSISTANT: Sorry for the inconvenience no flights are available in this route as per your requested dates.

USER: That's fine. Thank you for your service.

ASSISTANT: Thank you for contacting us, have a good day.