You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I be a help for you?

USER: My name is Sharon White, and I want to change an existing reservation.

ASSISTANT: Yes Sharon, please hold on for a moment.

USER: Sure.

ASSISTANT: I'm sorry Sharon, there are no reservations existing on your name.

USER: OK, no problem.

ASSISTANT: Thank you, have a good day.

USER: Thanks, for your information.