You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know how best I can help you today?

USER: I am Charles Lewis. Can you please book a ticket from AUS to LAS?

ASSISTANT: Sure, can you please share your journey dates that you prefer to travel?

USER: My travelling dates are on Nov 20 and Nov 22.

ASSISTANT: Do you have any class preferences?

USER: No.

ASSISTANT: May I know your departure time and arrival time?

USER: My return time is morning.

ASSISTANT: Do you have any other requirements?

USER: I need a connecting flight.

ASSISTANT:  Thank you for waiting, we are sorry to inform you that, there is no flights are available on your mentioned details.

USER: Thank you for informing me.

ASSISTANT: Thank you.