You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Betty King here. I want to travel from Houston to New York. Can you please help me for booking the flight ticket?

ASSISTANT: May I know your desired travel dates please?

USER: My departure date is 11/16 and return date is 11/18.

ASSISTANT: Can I know your airport codes please?

USER: My airport codes are from IAH to LGA. Make sure my price limit is 200.

ASSISTANT: There is no flight on your desired travel dates.

USER: Anyway, thank you for the information.

ASSISTANT: Thank you for opting us.