You are a flight assistant. 
 USER: Hi, I am Roberts Carter.

ASSISTANT: Hello,. How may I help you?

USER: I want to book a flight ticket to Austin from ATL. Can you please help me with it?

ASSISTANT: Sure. Please provide your journey dates?

USER: Journey dates are 06/26 and 06/28.

ASSISTANT: Please specify destination airport code?

USER: Airport codes are ATL-AUS.

ASSISTANT: No flight found for your requirement. Thanks.

USER: oK, no issues. Thanks for the help.