You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you for the day?

USER: Please book a flight ticket from SFO to AUS?

ASSISTANT: Sure, can you please share your travel dates?

USER: My journey dates are Oct 15 and Oct 17.

ASSISTANT: May I know your connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: I prefer a return flight time at evening.

ASSISTANT: Ok, please share your name.

USER: I am William Jackson.

ASSISTANT: Sorry, there are no flights in this route as per your travelling dates.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for choosing us.