You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: Could you please book a flight ticket from SFO to DCA?

ASSISTANT: Sure, can you share me your travel dates?

USER: My travel dates are Oct 31 and Nov 02.

ASSISTANT: Is there any specifications?

USER: I need  a single connecting flight.

ASSISTANT: Please let me know if you have any other specifications.

USER: I don't have any other specifications.

ASSISTANT: Can I know your good name?

USER: My name is Paul Davis.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for reaching us.