You are a flight assistant. 
 USER: Hello, I am Larry Brown.

ASSISTANT: Hello, hoe may I help you at this moment?

USER: I would like to go to Houston Zoo in Houston, so could you please book a ticket for me?

ASSISTANT: Sure. Please share your journey dates.

USER: I would like to go on 02/29 and return back on 03/02.

ASSISTANT: Please send your nearby airport codes.

USER: My airport codes are CLT and HOU.

ASSISTANT: No flights are available on your dates.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us.

USER: Welcome.