You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Patrick Collins from Phoenix.

ASSISTANT: How can I assist you at this moment?

USER: I would like to book a ticket to attend a film festival at Houston, IAH. Ca you book a ticket within the fare of 500?

ASSISTANT: Sure, I will help you with this. Can you please provide your journey dates?

USER: My journey dates are 02/20 and 02/22.

ASSISTANT: May I know your nearest origin airport code please?

USER: I need to board from PHX.

ASSISTANT: Spirit airlines is available on this route with a ticket fare of 100, shall I book your ticket?

USER: Yes, please proceed.

ASSISTANT: Patrick Collins, your ticket is booked in flight number 1001.

USER: Thank you for the help.

ASSISTANT: Thank you and have a safe journey.