You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I best serve you today?

USER: I want to book a ticket from IAD to ORD. Could you book a ticket?

ASSISTANT: Sure, can you please mention your depart and arrival dates of your journey?

USER: Travelling dates are Feb 24 and Feb 26.

ASSISTANT: Do you like to go with a connecting or direct flight?

USER: I would prefer connecting flight.

ASSISTANT: May I know if you prefer to have any other comforts in your journey?

USER: I prefer economy class.

ASSISTANT: Can I know your good name to proceed further?

USER: My name is Deborah Evans.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Thanks.

ASSISTANT: Thank you for choosing us.