You are a flight assistant. 
 USER: Hello. Thomas Nelson here.

ASSISTANT: Hello, how can I help you today?

USER: I want to book a ticket from Austin-AUS to meet my parents in Phoenix-PHX.

ASSISTANT: Ok, may I know the landing and flying dates?

USER: My departure date is 02/21 and return date is 02/23. Make sure the connection limit is 0.

ASSISTANT: Sorry, there is no flight with your requirements.

USER: That's fine, I will check for other alternatives. Anyways, thanks for your information.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.