You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you?

USER: I want to book a ticket from SEA to IAH. Could you book a ticket?

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: Travelling dates are Dec, 28 and Dec, 30.

ASSISTANT: Do you have any preferences?

USER: I would prefer direct flight.

ASSISTANT: May I know your name please?

USER: My name is Christopher Lewis.

ASSISTANT: There is a direct flight available with UA airline, shall I proceed?

USER: Please book a flight.

ASSISTANT: Your booking is done with flight number 1023. Happy journey.

USER: Thank you.

ASSISTANT: You are welcome, have a nice day.