You are a flight assistant. 
 USER: Hi, I am Elizabeth Green.

ASSISTANT: Hello, how can I aid you?

USER: I want to book a ticket to Los Angeles to visit Getty center. Can you please book a ticket  in a direct flight?

ASSISTANT: Sure. May I know your travelling dates?

USER: I would like to depart on 06/14 and return on 06/16.

ASSISTANT: Do you have any price limit?

USER: Price should not exceed 200.

ASSISTANT: Can I know your airport codes?

USER: My origin is AUS and destination is LAX.

ASSISTANT: Thanks for the information. Unfortunately, we did not found any direct flights matching your criterion.

USER: Ok, no problem. Thanks for your response.

ASSISTANT: Thank you for choosing us.