You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Susan Rodriguez here. Can you please book a ticket from ATL to OAK?

ASSISTANT: May I know your trip dates?

USER: Sure, my planned departure and return travel dates are 23rd and 25th of December.

ASSISTANT: Do you need any halt in your journey?

USER: I'm ok with direct flight as well as single connected flight.

ASSISTANT: Sorry to inform you that, there are no flights available with your requirements.

USER: That's ok, thank you for giving the information.

ASSISTANT: Thank you.