You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: Rebecca Wright here. I would like to book a ticket from AUS to DCA, can you please help me with that?

ASSISTANT: Sure, can I know your preferable dates?

USER: The travel dates are from 08/30 to 09/01.

ASSISTANT: Sorry, no flights available for given schedule.

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

ASSISTANT: Thank you for reaching us.