You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you?

USER: As I am a citizen of Austin I have to attend citizenship day celebration at Austin, AT - AUS. Will you assist me for booking a ticket for Austin, from DEN?

ASSISTANT: Sure, Please help me with your travel dates.

USER: Sure, my preferred journey dates are on 08/07 to 08/09.

ASSISTANT: May I know your name?

USER: Sure, my name is Donald Davis.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, I will choose another alternative to go. Thank you.

ASSISTANT: Thank you for opting us.