You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: Can you please book a flight ticket from DEN to DCA?

ASSISTANT: Sure, can you please provide your journey dates?

USER: Sure, my journey dates are Sept 22 and Sept 24.

ASSISTANT: Are you looking for any preferred connections?

USER: I need a connecting flight.

ASSISTANT: Do you have any other specifications to be met?

USER: No.

ASSISTANT: Can I have your name to proceed further?

USER: Sure, I am Frank Hernandez.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Thank you for your valuable time, unfortunately no flights available on that route.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for approaching us.