You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: My name is John Scott. I am planning to book a flight ticket from CLT to ORD. Can you book me a flight ticket?

ASSISTANT: May I know your travelling dates please?

USER: My travelling dates are from 09/08 to 09/10. I need my ticket fare should be within 200.

ASSISTANT: I am sorry, there are no flights with your requirements.

USER: It's ok. Thank you.

ASSISTANT: Welcome.