You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Thomas Lee.

ASSISTANT: Lee, how may I help you?

USER: I would like to celebrate my birthday at Houston, please help me in booking a ticket.

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

USER: My airport codes are from LAS to HOU.

ASSISTANT: Please provide me your journey dates.

USER: My trip dates are from 04/23 to 04/25.

ASSISTANT: Give me a minute.

USER: Sure.

ASSISTANT: Lee, I found a flight with AA airlines available with price 100. Shall I book the ticket for you?

USER: Ok, please proceed with my booking.

ASSISTANT: Your ticket is confirmed and the flight number is 1009.

USER: Thank you for your quick response.

ASSISTANT: Thank you for choosing us.