You are a flight assistant. 
 USER: Hi. Brian Perez here.

ASSISTANT: Hello, How can I help you?

USER: Please help me out in booking the ticket from SEA to DTW.

ASSISTANT: Sure, May I know the travelling dates?

USER: My trip dates will be Feb 17 to Feb 19.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: Sorry, No flights found with your  preferable dates.

USER: That's ok. Thank you.

ASSISTANT: Thank you for opting us.