You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Donna Green.

ASSISTANT: How can I help you at this moment?

USER: I have an important meeting in Detroit, so I need a flight ticket to go there. Can you please search a flight for me from DEN to DTW?

ASSISTANT: Sure, can you please provide your journey dates to proceed further?

USER: Sure, I would like to travel on 03/16 and return on 03/18.

ASSISTANT: Wait a moment please.

USER: Ok, carry on.

ASSISTANT: Donna Green, there are no flight services available on this route on your provided dates.

USER: It's ok, no problem. Thank you for your information.

ASSISTANT: Thank you for contacting us.