You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what help can I do for you?

USER: I want to visit Detroit, MI-DTW to meet my brother.Can you please help me for booking the flight ticket?

ASSISTANT: Sure, may I know your destination airport code?

USER: The destination airport code is MI-DTW.

ASSISTANT: Ok, can you provide the source airport code?

USER: The source code is from WA-SEA.

ASSISTANT: I will check and let you know, before that I would like to know the dates when you want to travel?

USER: Sure, the travelling dates are from 03/24 to 03/26.

ASSISTANT: May I know your know your good name please?

USER: My name is Ruth Thompson.

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

USER: Ok, no problem. I will search another way to complete my trip.

ASSISTANT: Thank you for contacting us.

USER: Thank  you for your information.

ASSISTANT: Have a great day.