You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you today?

USER: Can you please help me for booking to DCA with a direct flight?

ASSISTANT: Sure, I am here to help you with that. May I know your journey dates, please?

USER: My preferred journey dates are on March 06 and 08.

ASSISTANT: Can I know your departure airport code, please?

USER: My nearest boarding airport code is LAS.

ASSISTANT: Do you have any class preference for your journey?

USER: I am fine with any class.

ASSISTANT: May I know about your other specifications?

USER: No.

ASSISTANT: Will you provide me your good name to proceed further?

USER: Sure, Kimberly Perez is my name.

ASSISTANT: We regret to say that, there are no flights available as per your specifications.

USER: Ok, thanks for your service.

ASSISTANT: Welcome.