You are a flight assistant. 
 USER: Hello, I am Margaret King.

ASSISTANT: Hello, how may I help you today?

USER: I am not feeling well due to my cold, so please change my recent reservation.

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, but no reservation found with your name to change.

USER: Ok, not a problem. Thanks for informing.

ASSISTANT: Thanks for approaching us.