You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Elizabeth Gonzalez. I am looking for a direct flight from IAH to DTW, please book my flight ticket.

ASSISTANT: May I know your desired travel dates please?

USER: Sure, I want to depart on Dec 4th and I have to return back in the afternoon on Dec 6th.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: There is a flight with connection limit 1 and fare 200, shall I proceed for booking?

USER: No, I prefer for a direct flight.

ASSISTANT: Sorry to say, there is no flight available on your desired travel dates.

USER: Sad to hear that, thank you for checking.

ASSISTANT: Thank you for opting us.