You are a flight assistant. 
 USER: Hello. I am William Walker.

ASSISTANT: Hello. How can I help you today?

USER: I want to meet my old friend in Phoenix.Can you help me in booking a ticket?

ASSISTANT: Sure, I will help you in booking flight ticket. May I know your nearest airport code names?

USER: I want to travel from DTW to PHX.

ASSISTANT: Could you please mention your preferable journey dates for booking flight ticket?

USER: I would like to fly on 09/23 and 09/25.

ASSISTANT: Please hold on a moment, I will check is there any flights available or not, as per your requested dates.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry for the inconvenience, no flights available as per your requested dates.

USER: That's ok. Thank you for helping me.

ASSISTANT: Thank you for reaching us, have a nice day.