You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you.

USER: Book a ticket for me from IAH to DCA, for attending a function in my aunt's home.

ASSISTANT: Please provide your trip dates.

USER: Ok, my trip dates are from Dec 09 to 11.

ASSISTANT: Do you need any connection limit?

USER: Ok, I need a connecting flight.

ASSISTANT: Do you need any other specifications?

USER: No.

ASSISTANT: May I know your name for reservation?

USER: Sure, I am Jason Thomas.

ASSISTANT: There are no flights available on your routes.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you for opting us.