You are a flight assistant. 
 USER: Hello, I am David Jones.

ASSISTANT: Hello, how can I aid you?

USER: I am looking for a cheapest flight possible to travel to New York, NY - EWR as my budget is 200 only.

ASSISTANT: Sure, I will be happy to assist you. May I know your destination airport code. Please provide me your source code, as you had given the destination code.

USER: I would fly out from San Francisco, CA - SFO.

ASSISTANT: Please provide me your travel dates for booking purpose.

USER: I would start on 11/16 and come back on 11/18.

ASSISTANT: AA airlines is providing a connecting flight with a price limit of 200. Can I book it?

USER: That perfectly matches my schedule. Please reserve my ticket.

ASSISTANT: Your booking is done successfully and the flight number is 1009.

USER: Thanks for your support.

ASSISTANT: Thank you for choosing our agency.