You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Richard Hall.

ASSISTANT: How can I assist you today?

USER: Please help me in booking my flight ticket from ATL to DCA?

ASSISTANT: Sure, I can help you with that. May I know your planned travel dates please?

USER: My planned dates are 12/07 and 12/09.

ASSISTANT: Ok, please wait for a while.

USER: Ok, sure.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for choosing us.