You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Myself Sarah Harris. I want to meet my childhood friend's at Detroit. Can you please help me in booking the ticket from ORD to DTW?

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

USER: I will drop-off 12/19 and again I will be return back on 12/21.

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

USER: Not a big deal, anyhow thank you very much for your service.

ASSISTANT: You are welcome.