You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: I am planning to book a flight ticket to AUS from ATL, can you please help me out?

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

USER: Sure, my trip dates are July 30 and Aug 01.

ASSISTANT: Do you have any preferences?

USER: Yes, I am looking for a direct flight.

ASSISTANT: May I know your name please?

USER: Sure, my name is Helen Perez.

ASSISTANT: Sorry, there is no flight available with your requirements.

USER: It's ok, thank you for the information.

ASSISTANT: You are welcome, have a nice day.