You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Lisa Moore from Denver.

ASSISTANT: How can I assist you today?

USER: Can you please help me in flight ticket booking process from DEN to AUS?

ASSISTANT: Sure, I can help you with that. May I know your planned departure and return travel dates please?

USER: Thank you for your response, I want to take off on June 09 and book my return ticket also on June 11.

ASSISTANT: Ok, may I know your class preference please?

USER: I am ok with any class.

ASSISTANT: Which airlines do you prefer to travel?

USER: I want a normal cost airline so please check with this.

ASSISTANT: Sure, please let me know if you have any other specifications.

USER: I want to depart in evening time so also check with this.

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates with your given details.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: Thank you for choosing us, have a great day.