Hi.
user
Hello. How can I  help you?
assistant
My wedding venue has been changed, so I want to amend my existing reservation. Could you help me out?
user
May I know your name please?
assistant
Ok, my name is Mark Smith.
user
I am sorry no reservation found on your name.
assistant
Ok, no problem. Thank you for your help.
user
Thank you for choosing us.
assistant