You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: Can you please help me to book a flight ticket from PHX to DEN?

ASSISTANT: Sure, may I know the planned travel dates?

USER: Sure, my planned travel dates are Aug 19 and Aug 21.

ASSISTANT: May I know the time concerns?

USER: I want afternoon flight for my return journey.

ASSISTANT: May I know the class preference?

USER: I prefer business class for my journey.

ASSISTANT: Is there any connection limit?

USER: I am looking for a connecting flight.

ASSISTANT: Please provide me the name.

USER: Myself Kathleen Allen.

ASSISTANT: Sorry, there are no flights are available for your desired intent.

USER: That's fine, not an issue. Anyway thank you for checking.

ASSISTANT: Thank you for reaching us.