You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: Can you  please help me with booking flight ticket from DEN to BOS?

ASSISTANT: May I know your trip dates?

USER: My trip dates are May 03 to May 05.

ASSISTANT: Do you prefer a direct or connecting flight?

USER: I need a direct flight.

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

USER: No, I don't have any other specifications.

ASSISTANT: Can I have your name please?

USER: My name is Robert Martinez.

ASSISTANT: Sorry to inform you that unfortunately there is no flights available by the given details.

USER: That's fine, thank you for the information.

ASSISTANT: Thank you.