You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: Please help me to book a flight ticket from DCA to ORD.

ASSISTANT: Sure, I can help you. May I know your travel dates?

USER: My journey dates are from Aug, 13 to Aug, 15.

ASSISTANT: Thank you. Please help me with your name.

USER: Samuel Young.

ASSISTANT: Are you comfortable with economy class flight or business class flight?

USER: I am happy with any class.

ASSISTANT: Do you prefer for a direct flight or a connecting flight?

USER: I need a single connecting flight.

ASSISTANT: Noted, please wait for a while. Let me check.

USER: Sure.

ASSISTANT: There is a flight having single connection with Southwest Airlines and the ticket fare is 100 only in economy class. Flight departs at 18:00 hours and arrives at 12:00 hours. Shall I book the ticket for you?

USER: Please proceed.

ASSISTANT: Your ticket is booked and your flight number is 1009.

USER: Thank you.

ASSISTANT: You are welcome and thank you for choosing us.