You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Timothy Johnson.

ASSISTANT: How can I help you?

USER: Can you help me in booking from AUS to DCA, as there is a business meeting to attend at Washington?

ASSISTANT: Sure, I will help you to book a flight. Can you please share me your travelling dates?

USER: My journey dates are 04/16 to 04/18.

ASSISTANT: Please allow me a moment.

USER: Sure.

ASSISTANT: Sorry, no flights are available on your route.

USER: No issue, thank you.

ASSISTANT: Welcome, have a nice day.