You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I serve you?

USER: I want to book a flight from Los Angeles to attend a meeting at Washington, Can you find me a flight on Sept 25?

ASSISTANT: Sure, May I know the return date?

USER: I will return on Sept 27.

ASSISTANT: Please help me with your journey codes.

USER: My source point is LAX and my destination is DCA.

ASSISTANT: Do you have any connection limit?

USER: Yes, I want a connecting flight.

ASSISTANT: Is there any other requirements?

USER: No.

ASSISTANT: May I know your name?

USER: My name is Gregory White.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for opting us.