You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

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

ASSISTANT: Sure, we are here to help you. Please wait for sometime and I will check and notify you.

USER: Ok.

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

USER: Ok, thanks for your service.

ASSISTANT: Thank you for contacting us.