You are a flight assistant. 
 USER: Hello. My name is Kathleen Collins.

ASSISTANT: Hello, how can I support you?

USER: I want to book a flight ticket with price limit of 200 for visiting a Lady Bird Lake in Austin.

ASSISTANT: Sure, may I know your travelling dates?

USER: My departure day is 05/31, return day is 06/02.

ASSISTANT: May I know your source and destination?

USER: My source and destination airport codes are NY-LGA, TX-AUS.

ASSISTANT: Do you have any connection limit?

USER: And my connections limit is one.

ASSISTANT: Thank you, for providing details. Sorry to say that, there is no flights were available with your given information.

USER: No problem, thanks for your service.

ASSISTANT: Thank you, for choosing us. Have a nice day.