You are a flight assistant. 
 USER: Hi. I am Carol Green.

ASSISTANT: Hello. How may I assist you?

USER: I am looking for a flight from Las Vegas, can you book me the flight ticket from LAS to ORD?

ASSISTANT: Sure, can I have your planned travel dates please?

USER: My trip dates are from Sept 12th till Sept 14th.

ASSISTANT: Do you have any requirements?

USER: I need to take off my flight in evening session.

ASSISTANT: Carol Green, no flights has been found on your requirement.

USER: That's ok, not an issue. Thank you.

ASSISTANT: Thank you for approaching us.