You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Myself Donna Thompson. I am planning to meet my brother at New York, will you help me in booking the flight ticket from DFW to EWR?

ASSISTANT: May I know your desired travel dates please?

USER: My travelling dates are Dec 28 and Dec 30.

ASSISTANT: Sorry to say, there is no flight on your desired travel dates.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for opting us.