You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: I am planning to meet my school friend in Denver, so please book a flight ticket from AUS to DEN.

ASSISTANT: Sure, please share me your trip dates.

USER: I will start on Dec 24, return on Dec 26.

ASSISTANT: Is there any class preferences for you?

USER: No.

ASSISTANT: Do you need direct flight or connecting flight?

USER: I need a connecting flight.

ASSISTANT: Please share me your other specfications.

USER: I do not have any other requirements.

ASSISTANT: Please mention your good name.

USER: My name is Cynthia Taylor.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: Not an issue, thank you.

ASSISTANT: Thank you for opting us.