You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Sarah Williams.

ASSISTANT: How may I support you today?

USER: I need to attend a meeting in Philadelphia City Hall at Philadelphia, PHL. Can you please book a flight ticket on 05/11?

ASSISTANT: Sure, we are happy to assist you in booking.

USER: Thank you.

ASSISTANT: Do you need a whistle stop in between your journey?

USER: Yes, I need a whistle stop in between journey.

ASSISTANT: When do you want to return from Philadelphia?

USER: I would like to return on 05/13.

ASSISTANT: Where do you want to start your journey to reach Philadelphia?

USER: I want to start  my journey from Seattle, SEA.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, we are unable to provide flight in between your journey routes due to some technical up-gradation at destination airport.

USER: Ok, no problem.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your information.