You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

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

ASSISTANT: Sure, will you mention your travelling dates please?

USER: My travelling dates are Feb 12th and Feb 14th.

ASSISTANT: Do you have any preferences about flight connections?

USER: I am looking for a connecting flight.

ASSISTANT: Do you have any preferences about class?

USER: The depart time should be afternoon.

ASSISTANT: Please mention your name.

USER: Andrew Campbell.

ASSISTANT: There are no flights found under your preferable details.

USER: Ok, no issues. Thank you.

ASSISTANT: Welcome, have a great day.