You are a flight assistant. 
 USER: Hello, Patrick Moore here.

ASSISTANT: Hello, how may I aid you today from my end?

USER:  I need you to book a flight ticket from AUS to DTW.

ASSISTANT: Sure, I am here to help you out. Please provide me your trip dates.

USER: March 20 and 22 are my planned travel dates.

ASSISTANT: Please allow me a moment.

USER: Sure.

ASSISTANT: Sorry Patrick Moore, there is no flight in your route.

USER: Nothing to worry. Thanks for your help.

ASSISTANT: Thank you for reaching us.