You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I'm Robert Hall. Can you please book me a ticket from AUS to SFO?

ASSISTANT: May I know your trip dates?

USER: My travel dates are 09/01 and 09/03.

ASSISTANT: Ok, please wait a minute. Sorry Robert, there is no flight on these dates.

USER: That's ok, thank you for your information.

ASSISTANT: Most welcome.