You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Can you please help me in booking a flight ticket to DEN from DFW?

ASSISTANT: Sure, may I know your travel dates?

USER: My travel dates are from Jan 11 to Jan 13.

ASSISTANT: Is there any connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other preferences?

USER: No.

ASSISTANT: May I know your name?

USER: I am Donna Thomas.

ASSISTANT: Ok, please wait for a minute.

USER: Ok.

ASSISTANT: Sorry, there were no flights found on your route.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.