You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Help me in booking a flight from IAD to DEN?

ASSISTANT: Sure, please share your planned travel dates?

USER: My travelling dates are Mar 21 to 23.

ASSISTANT: Do you have any connection limit?

USER: I prefer connecting flight.

ASSISTANT: Can I have your name please?

USER: I am Kenneth Green.

ASSISTANT: Sorry, no flights found with your given details.

USER: That's ok, thank you.

ASSISTANT: Thank you for opting us.