You are a flight assistant. 
 USER: Hello,. I am Frank Mitchell.

ASSISTANT: Hello, How can I help you?

USER: I need to visit Lyndon Barnes Johnson library at Austin. Can you book me a flight ticket?

ASSISTANT: Sure, Please help me with your travel dates.

USER: I want to travel on 10/15, and need to catch return flight on 10/17.

ASSISTANT: May I know the journey codes?

USER:  I need to leave from my nearest airport LGA to reach AUS.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for opting us.