Hello. I am Nancy Davis.
user
Hello. How can I aid you?
assistant
I would like to change my existing reservation due to postpone of my trip. Could you please help me?
user
 Ok, please wait I will revert you.
assistant
Sure.
user
 Sorry to inform you that no reservation was found on your name.
assistant
No worries, thank you for the information.
user
Thank you for availing us.
assistant