You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you today?

USER: I want to book a ticket from PHX to AUS. Could you book a ticket?

ASSISTANT: Sure, I am gleeful to help you with that. May I know your travelling dates, please?

USER: Travelling dates are Dec, 6 and Dec, 8.

ASSISTANT: Do you have any particular time for departing and returning?

USER: I would like to depart in the morning time.

ASSISTANT: Which class do you prefer either economy or business?

USER: I would like to prefer business class.

ASSISTANT: Do you have any other specifications?

USER: I would be comfortable with single stop over.

ASSISTANT: Sorry for the inconvenience, there are no flights found on this route as per your travel dates.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: My name is Mark Miller.

ASSISTANT: Thank you for reaching us, have a great day.