You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: I want to attend a seminar on machine learning, so please book my ticket from CLT to DTW.

ASSISTANT: Sure, please share me your trip dates.

USER: My itinerary dates are Sept 21 and 23.

ASSISTANT: May I know your class preferences?

USER: I am comfortable with any class.

ASSISTANT: For booking, we need your good name. Please mention it.

USER: Debra Anderson here.

ASSISTANT: Do you need direct flight or connecting flight?

USER: I need a connecting flight.

ASSISTANT: We found a Hawaiian airline and 1002 is flight number with a fare of 700. Shall I proceed?

USER: I want to return from Detroit in the afternoon.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: No problem, thank you.

ASSISTANT: Thank you for opting us.