You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Angela Carter. I have planned a trip with my friends to go Detroit so please help me with flight ticket booking from Las Vegas.

ASSISTANT: Sure, may I know your travel dates?

USER: Thank you. I have planned to travel on dates of Mar 22 and Mar 24.

ASSISTANT: Do you have any specification?

USER: Yes, I wanted to depart in afternoon time.

ASSISTANT: Sorry, there is no flight on your details.

USER: LAS and DTW are the airport codes of my locations, please check once again with details for flight availability.

ASSISTANT: I have checked this airport codes but there is no flight available on your route.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Thank you.

USER: Most welcome.