Hello.
Hello, how can I aid 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, I can change your reservation right now. Before that I need to know your good name please?
I am Rebecca Allen.
  Thank you. Please stay online for a while, I will check your reservation status and let you know.
Sure.
Sorry to say that, there is no active reservation found on your name.
No problem, thank you for checking.
Thank you for choosing us.