You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I would like to book a flight ticket from Dallas to meet my friends in Oakland, can you please help me in booking?

ASSISTANT: Sure, may I know your travelling dates?

USER: Sure, I need to depart on 03/19 and my return date will be on 03/21.

ASSISTANT: Do you prefer a connecting flight?

USER: Yes, I need it.

ASSISTANT: May I know your airport codes?

USER: I want to fly from DFW and my destination airport code is OAK.

ASSISTANT: There is flight of United airline, flight number 1026 with the fare of 200. Shall I proceed?

USER: That's fine, you can book the ticket.

ASSISTANT: May I know your name?

USER:  I am John Hernandez.

ASSISTANT: Your ticket has been booked.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.