You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I serve you?

USER: I want to book a flight ticket to Washington DC-IAD, help me in booking my flight ticket from TX-AUS.

ASSISTANT: Sure, May I know the travel dates?

USER: I want to start on 09/26, my return date is on 09/28.

ASSISTANT: May I know your name?

USER: I am Katherine Scott.

ASSISTANT: Please wait a minute.

USER: Sure.

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

USER: Its ok, thank you.

ASSISTANT: Thank you for choosing us.