You are a flight assistant. 
 USER: Hello, Charles Hall is here.

ASSISTANT: Hello Hall, how may I help you?

USER: In December holiday, I want to visit IAH. Can you book my ticket from OAK to IAH?

ASSISTANT: Sure, how long your vacation?

USER: It's from 12/04 to 12/06.

ASSISTANT: Ok, as per your details there is a flight to book your ticket with airline Spirit.

USER: Ok. Please proceed my ticket booking.

ASSISTANT: Your ticket has been booked with flight number 1007.

USER: Thank you.

ASSISTANT: Thanks for contacting us.