You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: My origin airport code is OAK and planning to book a plane ticket to IAD, please help me out.

ASSISTANT: Sure, I am delighted to help you. Can you please share your preferable dates to travel?

USER: Thanks. Sure, I am planning to travel from 03/10 to 03/12.

ASSISTANT: May I know your good name please?

USER: Sure, my name is Paul Phillips.

ASSISTANT: Sorry to inform you that there is no flight available in this route on your requested dates.

USER: It's ok, thank you for the information.

ASSISTANT: Most welcome. Have a great day.