You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, I am here to help you with this.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Myself Shirley Jones.

ASSISTANT: Ok, wait for a mean while please.

USER: Ok.

ASSISTANT: Sorry to say, that there is no active reservation found on your name to change it.

USER: Not an issue. Thank you.

ASSISTANT: You are welcome.