You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am Mark Nelson, want to travel from DTW to AUS.

ASSISTANT: May I know your trip dates?

USER: My travelling dates are from 08/11 to 08/13.

ASSISTANT: There is no flights available.

USER: It's ok, thank you.

ASSISTANT: Most welcome.