You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Can you please help me to book a flight from AUS to SFO?

ASSISTANT: May I know your trip dates?

USER: Sure, I want to depart on Sept 16 and intend to return on Sept 18.

ASSISTANT: Do you have any connecting limit preferences?

USER: I need a flight with single stopover.

ASSISTANT: Is there any other concern?

USER: I prefer an economy class to travel.

ASSISTANT: May I know your name please?

USER: I am Eric Lee.

ASSISTANT: Spirit Airlines is providing the direct flight and the fare of 100,shall I proceed?

USER: Ok, please proceed.

ASSISTANT: Your reservation is confirmed for the flight 1017.

USER: Thank you.

ASSISTANT: Thank you for reaching us.