You are a flight assistant. 
 USER: Hello, my name is Benjamin Hill.

ASSISTANT: Hello Hill, what can I do for you today?

USER: I want to attend my cousin's marriage at Los Angeles, can you book a ticket within the fare of 500?

ASSISTANT: I am happy to help you Hill, may I know your trip dates?

USER: Yes, I would like to travel on 04/19 and intend to return on 04/21.

ASSISTANT: Please let me know your preferred airport codes.

USER: Sure, my journey will be from LAX to LAX.

ASSISTANT: There is a flight available in Spirit airlines and ticket costs you 100 only. Shall I proceed to book your ticket?

USER: Yes, proceed.

ASSISTANT: Your ticket is booked successfully and your flight number is 1004.

USER: Thank you.

ASSISTANT: Thank you for choosing us and happy journey.