You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you now?

USER: Please book a ticket from SEA to IAD to go for Science festival.

ASSISTANT: Sure, I can help you and can I know your preferable travel dates?

USER: My travelling dates are Oct 27 and Oct 29.

ASSISTANT: Please provide your connection limit preference.

USER: I want a direct flight.

ASSISTANT: Can I know your name for booking your flight ticket?

USER: Sure, I am Scott Hall.

ASSISTANT: I regret to inform you that there is no direct flight obtained on your journey dates to book a flight ticket for your journey.

USER: Ok, no issues. Thank you.

ASSISTANT: You are welcome and thank you for contacting us.