You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to attend for an interview in Washington, so please book a flight ticket from DTW to IAD.

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

USER: I want to fly on Dec 21, return on Dec 23.

ASSISTANT: May I know your connection limit?

USER: I need a single connecting flight.

ASSISTANT: Is there any class preference for you?

USER: No.

ASSISTANT: Your good name please.

USER: My name is Frank Lee.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: We found an airline: Southwest, flight number: 1016 and price is 100 with one connection.

USER: Ok, proceed to booking.

ASSISTANT: Your flight ticket has been reserved.

USER: Thank you.

ASSISTANT: Thank you for reaching us.