You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I want to book a flight ticket from CLT to BOS. Could you help me in booking?

ASSISTANT: Sure, I am here to help you. May I know your travel dates please?

USER: My travelling dates are from Dec 19-21.

ASSISTANT: Ok, do you have any other specifications?

USER: I need direct flight.

ASSISTANT: Ok, hold on for a moment. Let me check the best available flight for you.

USER: Ok.

ASSISTANT: May I know your name please?

USER: Jack Brown here.

ASSISTANT: Sorry Jack Brown, there are no flights available on your requested dates.

USER: That's ok, no problem. Thank you.

ASSISTANT: Welcome, thank you for choosing us. Have a great day.