You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I am planning to visit Boston, will you help me in booking the flight ticket from DCA to BOS?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My travelling dates are Feb 02 and Feb 04.

ASSISTANT: Can I know your name please?

USER: Myself Anthony Smith.

ASSISTANT: Do you need any specifications?

USER: I need a flight with single connection.

ASSISTANT: Can I know your other preferences?

USER: I don't have any other specification.

ASSISTANT: Sorry, there are no flights found.

USER: Ok, not an issue.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your information.