You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you help me in booking a flight ticket from DEN to IAD?

ASSISTANT: I am glad to help you with your concern.

USER: Thank you.

ASSISTANT: Can you please let me know your trip dates?

USER: I want to start on 11/28, and return on 11/30.

ASSISTANT: Do you have any connection limit preference?

USER: Yes, I need  a break in my journey.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: Do you have any airline preference?

USER: No.

ASSISTANT: Do you have any specific time concern?

USER: No, I am comfortable with above requirements.

ASSISTANT: Could you help me with your name please?

USER: I am Michael Brown.

ASSISTANT: Thank you for sharing all your necessary details, Michael Brown. Please allow me 2-3 minutes while I check with the availability of flights.

USER: Sure.

ASSISTANT: Thank you for waiting, Michael Brown. Sorry, there is no flight available for the mentioned dates.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for reaching us.