You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

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

ASSISTANT: Let me know your travel dates.

USER: My travelling dates are from Feb 26 - 28.

ASSISTANT: Do you have any preference?

USER: I prefer for connecting flight.

ASSISTANT: Can I know your name?

USER: Debra Gonzalez.

ASSISTANT: Sorry, no flights found for your travelling dates. Thank you.

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