You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to attend a marriage in Detroit. Can you please help me for booking the flight ticket?

ASSISTANT: Sure. Tell me your airport codes please?

USER: My airport codes are PHX and DTW.

ASSISTANT: Now please share your travel dates?

USER: My travelling dates are July 23 and July 25.

ASSISTANT: Are you looking for a stopover in your journey?

USER: I want to prefer direct flight.

ASSISTANT: Any other preferences?

USER: No.

ASSISTANT: Please wait.

USER: Ok, I will wait.

ASSISTANT: Thanks for your time.

USER: My pleasure.

ASSISTANT: Sorry presently direct flights are not available.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you.