Hi, I am Pamela Scott.
Hello, how may I assist you today?
As my plan to give a presentation at Phoenix but due to bad weather conditions I need to  change an existing reservation. Can you help me with this?
Sure, please wait a minute I will revert to you with current status.
Ok.
Unfortunately, there is no reservation found with your name.
That's ok, thanks for your information.
Thank you for availing us.