You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Virginia Thompson. Can you help me in booking the ticket from DTW to OAK?

ASSISTANT: May I know your journey dates?

USER: My planning dates are from 04/18 to 04/20.

ASSISTANT: Sorry, there is no flight is available for you.

USER: Ok. That's fine.

ASSISTANT: Thank you for choosing us, have a nice day.

USER: Anyway, thank you.