You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: Please help me to book a flight ticket from DCA to SFO?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: My departure and arrival dates are Jan 21 to Jan 23.

ASSISTANT: Ok, could I have your name please?

USER: Sarah Johnson.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need a connecting flight.

ASSISTANT: Ok, do you have any other specifications?

USER: No.

ASSISTANT: The economy class with flight number 1019 of American Airline is available having fare as 200 and connection as 1, is it ok for you?

USER: Ok, please proceed.

ASSISTANT: Ok, your reservation is confirmed. The departure time is 17:00 hours and the arrival time is 16:00 hours.

USER: Thank you.

ASSISTANT: You are welcome, have a great day.