You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: My name is Elizabeth Brown. I would like to travel from ORD to IAD, could you help me out?

ASSISTANT: May I know your trip dates?

USER: My preferable dates are from 07/14 to 07/16.

ASSISTANT: Sorry, there are no flights available as per your request.

USER: That's fine.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your time.