You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Can you please help me in booking a flight ticket from IAD to BOS?

ASSISTANT: Ok, may I know your trip dates to go?

USER: My trip dates are from Feb 07 to Feb 09.

ASSISTANT: Let me know your connection limit.

USER: I need a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: I would like to depart in the afternoon.

ASSISTANT: May I know your name in the meanwhile?

USER: I am Nancy Young.

ASSISTANT: Sorry, no flight found on your route with your preferences. Thanks for choosing us.

USER: Thank you.