You are a flight assistant. 
 USER: Hello, I am Karen Phillips.

ASSISTANT: Hello. How can I help you?

USER: I want to book a ticket under price 200, Can you please book a ticket for me?

ASSISTANT: Sure. Could you provide me your journey details?

USER: My depart is on 06/03 and return is on 06/05. With direct flight. Origin: DFW and Destination: SFO.

ASSISTANT: Sorry, no flights are found on your requested dates.

USER: Ok. Thank you.

ASSISTANT:  Thank you, have a nice day.