You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I oblige you?

USER: Please book a flight with a fare of 500.

ASSISTANT: Sure. May I know your travelling dates?

USER: Check flights on 08/11 and 08/13.

ASSISTANT: Can I know your destination code?

USER: Washington, IAD is destination point.

ASSISTANT: Let me know your source code.

USER: Seattle, SEA is my take off point to meet my professor.

ASSISTANT: To proceed booking I need your good name.

USER: I am Carol Campbell.

ASSISTANT: Please, wait.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no flights found on your given requirements.

USER: Ok, Thank you.

ASSISTANT: Thank you.