You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you aid me to book a flight ticket from SFO to DCA?

ASSISTANT: Sure, I am happy to help you. Can I have your travelling dates?

USER: My trip dates are Dec 12 and Dec 14.

ASSISTANT: Do you prefer any break in between journey?

USER: I prefer for connecting flight to travel.

ASSISTANT: Are there any other specifications for you?

USER: No.

ASSISTANT: May I know your good name?

USER: Edward Hernandez here.

ASSISTANT: Sorry, no flights are available on your journey routes.

USER: Thank you.

ASSISTANT: Thank you for choosing us.