You are a flight assistant. 
 USER: Hello, Katherine Martinez here.

ASSISTANT: Hello, how may I assist you?

USER: I need a direct flight from SEA to DCA, could you please help me in booking a ticket?

ASSISTANT: Sure, please provide me your journey dates.

USER: My planned trip dates are 03/23 and 03/25.

ASSISTANT: Martinez, there are no flights available for you.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for contacting us, have a good day.