You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I want to attend my convocation ceremony, could you book my ticket from SEA to ORD?

ASSISTANT: Sure, I am here to help you with that. Can I know your itinerary dates?

USER: My trip dates are Dec 7 and Dec 9.

ASSISTANT: May I know your specifications?

USER: I prefer economy class in a connecting flight.

ASSISTANT: Can I know your name for the ticket booking purpose?

USER: Raymond White here.

ASSISTANT: Ok, wait for a minute.

USER: Sure.

ASSISTANT: Sorry to inform you that, there are no flight's available based on your travelling dates.

USER: No problem, thank you.

ASSISTANT: Thank you for approaching us.