You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Nicholas White.

ASSISTANT: How can I assist you today?

USER: I am planning to have a round trip from Austin, can you please book me a ticket from AUS to AUS?

ASSISTANT: Sure, can you please share your travel dates?

USER: My preferable journey dates are from 09/11 to 09/13.

ASSISTANT: Let me check for the availability of flight.

USER: Sure, take your own time.

ASSISTANT: Nicholas, I am sorry to inform you that there is no flight available at your requested dates.

USER: Ok, not an issue. Thank you for providing information.

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