You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you?

USER: Can you please help me to book flight ticket from AUS to PHL?

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

USER: My preferred dates to travel are July 27 and July 29.

ASSISTANT: Do you have any preferences?

USER: I prefer a connecting flight.

ASSISTANT: May I know your name please?

USER: Patrick Lee here.

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

USER: It's ok, thank you.

ASSISTANT: You are welcome, have a nice day.