You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Catherine Gonzalez.

ASSISTANT: How may I help you?

USER: I love hiking at Angel Island at Oakland. Can you help me in booking a ticket from Houston?

ASSISTANT: Sure, may I know your airport codes please?

USER: I am planning my journey from IAH to OAK.

ASSISTANT: When would you like to start your journey?

USER: Please find the availability on dates 11/19 and 11/21.

ASSISTANT: I found a flight for you in Southwest airlines with price 100. Can I proceed?

USER: Sure, the price fits in my budget. Please book the ticket.

ASSISTANT: Ok, your ticket has been booked with flight number 1018.

USER: Thank you for your service.

ASSISTANT: Thank you for choosing us.