You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: I am Alexander Wilson. Can you please book a flight ticket from CLT to DTW?

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

USER: Yes, my travel dates are 04/19 and 04/21.

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

USER: That's ok, no problem. Thank you for your information.

ASSISTANT: Thank you for reaching us.