You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Stephanie Carter.

ASSISTANT: Nice to meet you Carter.

USER: I am planning to book a ticket to attend a meeting at DEN. Can you please help me out to book a ticket from IAD?

ASSISTANT: Sure, can I know your travelling dates please?

USER: I would like to travel on 09/09 and return back on 09/11.

ASSISTANT: Sorry, there is no flight available as per your request.

USER: That's fine. Thank you for your service.

ASSISTANT: My pleasure.