Hello.
user
Hello, how may I assist you today?
assistant
I am Alexander Nelson. I would like to change my existing reservation, due to postpone of my scheduled examination dates. Can you please help me?
user
Sure, I am here to help you.
assistant
Thank you.
user
Please hold on.
assistant
Sure.
user
Thanks for waiting, there is no active reservation found on your name.
assistant
Ok, no problem. Thank you for your information.
user
Thank you for  availing us.
assistant