You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Please book a flight ticket from DCA to LAX?

ASSISTANT: Sure, I am here to help you in booking. Can you please share your travel dates?

USER: My journey dates are June 19 and June 21.

ASSISTANT: Let me know your connection limit.

USER: I need a direct flight.

ASSISTANT: Do you have any specification?

USER: No.

ASSISTANT: May I know your name for further process?

USER: I am John Hall.

ASSISTANT: Sorry, no flights found on your given details.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for reaching us, have a nice day.