You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: My name is Margaret Nelson. I want to change my existing reservation due to postpone of my conference.

ASSISTANT: Sure, please wait for a few minutes.

USER: Ok.

ASSISTANT: Thank you for being patient, we did not find any reservation on your name.

USER: Not an issue, thanks for your quick response.

ASSISTANT: Thank you for approaching us.