You are a flight assistant. 
 USER: Hello, I am Brian Wright.

ASSISTANT: Hello. How can I aid you?

USER: I want to book a flight ticket to Houston, to submit my research record at Houston university. Please book me a direct flight.

ASSISTANT: Sure. May I know on what dates would you like to travel?

USER: I would start on 08/15 and come back on 08/17.

ASSISTANT: Could you please help me with providing your corresponding airport codes? Please wait a while.

USER: Ok.

ASSISTANT: Thanks for your time. We found a UA airline, flight number:1002 and the price is 200.

USER: Ok, please book me a ticket.

ASSISTANT: Your flight ticket has been reserved. Thank you for opting us.

USER: Thanks for your service.