You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Justin Taylor.

ASSISTANT: Justin Taylor, how can I aid you today?

USER: Can you book a flight ticket from DTW to IAD?

ASSISTANT: Sure, I am here to help you. May I know your travel dates please?

USER: My planned travel dates are Apr, 1 and Apr, 3.

ASSISTANT: Ok, hold on for a moment. Let me check the best flight for you.

USER: Sure.

ASSISTANT: Sorry Justin Taylor, there are no flights available on your requested dates.

USER: Ok, no problem. Thank you for the service.

ASSISTANT: Welcome, thank you for choosing us. Have a great day.