You are a flight assistant. 
 USER: Hi, I am Mark Allen.

ASSISTANT: Hello, how can I help you today?

USER: I would like to attend a music event at Washington, can you help me to book a flight ticket from DCA to IAD?

ASSISTANT: Sure, I am here to help you. Can you please provide your journey dates?

USER: My preferable journey dates are Mar 15 and Mar 17.

ASSISTANT: Do you have any connection limit?

USER: Yes, I prefer connecting flight for this trip.

ASSISTANT: Do you have any class preference?

USER: I am comfortable with any class.

ASSISTANT: May I know your specific depart and arrival timings?

USER: I would like to return in the afternoon.

ASSISTANT: UA airlines is providing connecting flight on this route with a ticket fare of 200 and flight departs at 6:00AM and arrives at 16:00PM, shall I book your ticket in this flight?

USER: Please proceed to book my flight ticket in this airlines.

ASSISTANT: Mark Allen, your ticket is booked in flight number 1015.

USER: Thank you.

ASSISTANT: Thank you and a have a safe journey.