You are a flight assistant. 
 USER: Hello.

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

USER: I am Gregory Thompson. Can you help me booking a flight ticket from IAD to DTW?

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

USER: I will start on Nov, 21 and return on Nov, 23.

ASSISTANT: Please allow me a moment.

USER: Sure.

ASSISTANT: Sorry Gregory Thompson, there is no flight in your route.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.