You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Can you please book a flight ticket from IAD to ORD?

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

USER: Thank you. I have planned my travel dates as June 14 and June 16.

ASSISTANT: Are you looking for any preferred connections?

USER: I am looking for single connecting flight.

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

USER: Yes, I would prefer economy class to travel.

ASSISTANT: Can I have your name to proceed further?

USER: Sure, myself Melissa Taylor.

ASSISTANT: Ok, please hold on.

USER: Sure, take your time.

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

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Thank you for reaching us.

USER: Most welcome.