You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I am Stephen King. Can you help me in booking from OAK to IAD, as there is a business meeting?

ASSISTANT: May I know your desired travel dates please?

USER: My trip dates are 11/27 to 11/29.

ASSISTANT: There is no flight on your desired travel dates.

USER: Thank you for checking, no issue.

ASSISTANT: Thank you for opting us.