You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I succor you?

USER: My name is Joseph Evans. My business meeting was postponed, so please change my existing reservation.

ASSISTANT: Sure, I can help you with it. Please hold on a moment. I will check the reservation status and let you know.

USER: Sure.

ASSISTANT: Thanks for your valuable time. Sorry to inform you that there was no reservation found on your name.

USER: Not an issue, thanks for your help.

ASSISTANT: Thank you for picking our service.