You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I be at your service today?

USER: Please aid me to book a flight from IAD to LAS.

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: I want to depart on Dec 31 and need to return on Jan 2.

ASSISTANT: Do you have any other specifications?

USER: I need a connecting flight.

ASSISTANT: Please help me with your name for booking.

USER: I am Stephen Davis.

ASSISTANT: According to your information, I have found a flight with single stop over in your journey with a minimum fare of 400 with flight number 1017. Shall I proceed with this flight?

USER: Ok, please proceed.

ASSISTANT: Your booking is done.

USER: Thank you.

ASSISTANT: Most welcome.