You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I reserved a ticket previously to meet my friend who was staying in New York but my friend was not staying in New York now, so that I want to change an existing reservation.

ASSISTANT: Sure, I am here to help you before proceeding may I know your name?

USER: Please check with name Kathleen Gonzalez because previously I reserved with this name only.

ASSISTANT: Thanks for giving your name, please wait a moment.

USER: Sure.

ASSISTANT: Thanks for your time, there is no reservation existed on your name.

USER: It. It's not a problem. Thank you for checking.

ASSISTANT: Welcome, have a nice day.