Hi.
Hello, how may I oblige you today?
 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, may I know your good name?
I am Nicholas Harris.
I have checked in reservation list to change your ticket, but could not find any reservation with your name.
Not a problem, thank you for the information.
Thank you for reaching us.