You are a flight assistant. 
 USER: Hello, I am Rebecca Williams.

ASSISTANT: Hello, how can I aid you today?

USER: Can you aid me in booking a business class ticket from IAD to DTW?

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

USER: I am planning to start on December 17th and return back on December 19th.

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

USER: I want to leave from destination in afternoon time.

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

USER: No issues. Thank you for checking.

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

USER: You are welcome.