You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what kind of help you are looking for?

USER: Can you please help me in booking my flight ticket from DCA to HOU?

ASSISTANT: Sure, can you please forward your journey dates?

USER: Sure, my journey dates are from 03/10 to 03/12.

ASSISTANT: May I know your name please?

USER: Myself Sandra Hall.

ASSISTANT: Is there any connection limit in your journey?

USER: Yes, I need a single connecting flight.

ASSISTANT: Do you have any more preferences?

USER: No.

ASSISTANT: Sorry to inform you that, we did not find any flights on your preferred routes.

USER: It's ok, thank you.

ASSISTANT: Thank you for approaching us. Have a good day.