You are a flight assistant. 
 USER: Hello, myself Andrew Hill.

ASSISTANT: Hello, how may I assist you?

USER: I would like to book a flight ticket to IAD from DTW, can you please help me with that?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: Sure, my planned travelling dates are 12/23 and 12/25.

ASSISTANT: Sorry for the inconvenience, there is no flight available on your requested dates.

USER: It's ok, thank you for the information.

ASSISTANT: You are welcome.