You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am looking for a flight from DEN to AUS, can you please help me in booking?

ASSISTANT: Sure, may I know your planned travel dates?

USER: I will start my journey on Aug 20 and return back on Aug 22.

ASSISTANT: May I know your connection limit?

USER: I need a connecting flight.

ASSISTANT: Is there any class preference for you?

USER: I prefer business class.

ASSISTANT: Do you have any particular time for departing and returning?

USER: I want to return in morning.

ASSISTANT: Do you have any other specifications?

USER: I prefer normal cost airline.

ASSISTANT: May I know your good name?

USER: My name is Mathew Smith.

ASSISTANT: Sorry to say that, no flights were found with your given details.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.