You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: I am planning to book a flight from DCA to reach Los Angeles, will you please help me in booking a flight?

ASSISTANT: May I know on which dates you are willing to travel?

USER: My planned dates are on Dec 3rd to 5th.

ASSISTANT: Do you require any stopovers in your journey?

USER: No, I prefer a direct flight.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: Sorry to inform you that unfortunately there is no flights available by the given details.

USER: No worries, I will choose another airline.

ASSISTANT: May I know your name?

USER: Sure, my name is Jennifer Scott.

ASSISTANT: Thank you.

USER: Thank you for your service.