Hello.
user
Hello, how may I assist you today?
assistant
I want to change my existing reservation, can you please help me with this?
user
Sure, may I know  your name for the changing  process?
assistant
I am Kimberly Anderson.
user
Sorry, as per your concern I can not amend your reservation, as your reservation is not found as per our records.
assistant
Ok, no problem. Thank you for your information.
user
Welcome, thank you for reaching us.
assistant