You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I want to book a flight ticket from PHX to IAD, can you please help me in booking?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My planned dates are Sept 1 and Sept 3 respectively.

ASSISTANT: Do you need any specifications?

USER: I am looking for a direct flight.

ASSISTANT: Can I know your name please?

USER: Gregory Roberts here.

ASSISTANT: Sorry, there are no flights found.

USER: That's fine, not an issue. Thank you for your help.

ASSISTANT: Thank you for reaching us.