You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I want to change my existing reservation, can you please help me with this?

ASSISTANT: Sure, I am here to help you with that. Can you please share your name?

USER: I am Cynthia Young.

ASSISTANT: Please allow me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no active reservation found on your name in our database.

USER: Ok, no problem. Thank you for your information.

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