Hi.
Hello, how may I help you?
Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?
Sure, I am here to help you with that, can I know your good name to proceed further?
I am Helen Nelson.
 I am very sorry to inform you that there is no reservation found under your name in our database.
No problem, thanks for the information.
Thank you for reaching us.