You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I would like to travel from LAX to DTW as a business trip.

ASSISTANT: Sure, may I know your trip dates please?

USER: My journey dates are 03/16 and 03/18.

ASSISTANT: Do you have any other requirements?

USER: Departure time should be evening.

ASSISTANT: Let me know your name please.

USER: Mary Martinez here.

ASSISTANT: Sorry, we regret to inform you that there is no flight available as per your request.

USER: No issue, Thanks for the information.

ASSISTANT: Most welcome.