You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is David Thomas.

ASSISTANT: How can I serve you today?

USER: I want to book a flight ticket from CA - OAK to TX - AUS. Please help me in booking a flight ticket.

ASSISTANT: Sure  David Thomas, I am here to assist you.

USER: Thank you.

ASSISTANT: On what dates you are willing to go?

USER: My travel dates are from 08/31 to 09/02.

ASSISTANT: Ok, please hold on.

USER: Sure.

ASSISTANT: Sorry, no flights found on your requested travelling dates.

USER: No problem, thanks for your information.

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