You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you?

USER: I have to visit Washington-DC, please help me to book my flight ticket from IAH to DCA.

ASSISTANT: Sure, please provide your trip dates.

USER: Thank you. I want to depart on Dec 12th and return back on Dec 14th.

ASSISTANT: Do you need any connection limit?

USER: I prefer for a flight having single connection.

ASSISTANT: Do you have any other requirements?

USER: I need business class ticket.

ASSISTANT: May I know your name?

USER: My name is Katherine Hill.

ASSISTANT: There are no flights available on your routes.

USER: Not an issue. Thank you for the information.

ASSISTANT: Thank you for choosing us.