Hi.
Hello, how can I help you?
 I just want to change an existing reservation as my meeting got post pone due to some technical issues. Can you help me?
Yes, I am here to help you. May I know your name please?
Thank you.
Ok, please wait a minute.
Sure, Mark Lewis.
Thank you for your time, sorry no reservation found on your name.
No issue.
Thank you for reaching us, have  a nice day.