You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you at this moment?

USER: Donald Davis here. I want to travel from ORD to AUS for attending a birthday function. Can you please help me for booking the flight ticket?

ASSISTANT: Sure Donald Davis, I will help you with that. Can I have your travel dates please?

USER: My departure date is 08/01 to 08/03.

ASSISTANT: Ok Donald Davis, please wait a moment.

USER: Ok, I will wait.

ASSISTANT: Sorry Donald Davis, no flight is available to you on your dates.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us, have a good day.