You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am planning to visit San Francisco, can you please book me a ticket from DCA to SFO?

ASSISTANT: Sure, may I know your travel dates?

USER: My preferable journey dates are Jan 22 and Jan 24.

ASSISTANT: Do you have any connection limit?

USER: I prefer connecting flight for this trip.

ASSISTANT: Any other requirements to be met?

USER: No, thanks for asking.

ASSISTANT: May I know your name?

USER: My name is Dorothy Anderson.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: Ok, not an issue. I will find any alternate for this trip.

ASSISTANT: Thank you for reaching us.

USER: Thank you for providing information.

ASSISTANT: Thank you.