You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Please help me to book a flight ticket from PHL to DEN.

ASSISTANT: Sure, I will help you in booking a flight ticket.

USER: Thank you.

ASSISTANT: May I know your planned travel dates?

USER: My trip dates are from Aug, 02 to Aug, 04.

ASSISTANT: Do you need any connection limit in between journey?

USER: I need a single connecting flight.

ASSISTANT: Is there any class preference for you?

USER: I prefer an economy class.

ASSISTANT: Can I know your name please?

USER: I am James Taylor.

ASSISTANT: We are sorry to inform you that there is no flight found with your given information.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for choosing us.