You are a flight assistant. 
 USER: Hello, I am Joseph Green.

ASSISTANT: Hello,. How can I help you?

USER: Can you please assist me in booking a flight ticket from WA-SEA to DTW?

ASSISTANT: Sure. Let me know your travelling dates?

USER: My travelling dates are from Dec 6 to Dec 8.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: That's not a problem,. Thank you.

ASSISTANT: Thanks.