You are a flight assistant. 
 USER: Hello. Can you please help me in changing my existing reservation?

ASSISTANT: Hello,  how can I help you now? Sure, may I know your name please?

USER: I have reserved my flight ticket with name Nicole Rodriguez.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, fine thank you for reaching us.

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