You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you please assist me to book a flight at this time?

ASSISTANT: Sure, may I know your source and destination airport codes?

USER: I will fly from AUS airport to reach LGA.

ASSISTANT: Can you please share your travel dates?

USER: My travel dates are May 25th and 27th.

ASSISTANT: Do you want connecting flight or direct flight?

USER: I am fine with a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: May I know your name please?

USER: My name is Patrick Lewis.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us.