You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you?

USER: Could you please help me in booking a flight ticket?

ASSISTANT: Sure, may I know your good name please?

USER: Yes, my source is from NV-LAS to NY-EWR. And, my travelling dates are 05/11 to 05/13. OK, my name is Jason smith.

ASSISTANT: Sorry Jason, there is no flight matching according to your request.

USER: OK,thank you.