You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

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

ASSISTANT: Sure, I can help you with that. May I know your travel dates please?

USER: My travel dates are from Sept 20 to Sept 22.

ASSISTANT: Can I have your good name please?

USER: I am John Parker.

ASSISTANT: May I know your connection limit please?

USER: I need a connecting flight.

ASSISTANT: Do you have any class and airline preference?

USER: I would like to travel in normal cost airline.

ASSISTANT: Please let me know if you have any other specifications.

USER: No.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates with your given details.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us, have a nice day.