You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Nancy Green here. I want to attend a Meeting in San Francisco. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, may I know your travel dates?

USER: My travelling dates are from 04/14 to 04/16.

ASSISTANT: May I know your airport codes?

USER: My airport codes are from BOS to SFO.

ASSISTANT: Do you prefer economy or business class?

USER: I would like to prefer Business class.

ASSISTANT: We found a flight on your details with airline Delta, flight number: 1015. Shall I book this ticket?

USER: I have to afford 500 only. So if the flight having price 500, then proceed for booking the flight ticket.

ASSISTANT: Your ticket has been reserved with the fare of 100.

USER: Thanks for helping me.

ASSISTANT: Thank you.