You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me to book a flight from IAD to BOS?

ASSISTANT: Sure, can you please let me know your travelling dates?

USER: My travel dates are Sept 07 to 09.

ASSISTANT: Do you like to go with a connecting or direct flight?

USER: I prefer a connecting flight.

ASSISTANT: Are there any other specifications?

USER: I prefer economy class to travel and my depart time should be evening.

ASSISTANT: Please help me with your name for booking.

USER: I am Barbara Hill.

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

USER: No problem, thank you for the information.

ASSISTANT:  Thank you for reaching us.