You are a flight assistant. 
 USER: Hello, I am Mary Moore.

ASSISTANT: Hello, Mary Moore. How can I assist you for the day?

USER: I recently reserved a ticket to give a visit to my best friend. But, before my journey he came to my home and gave me a surprise visit. So, now I want that ticket to change my reservation, Can you please help me?

ASSISTANT: Sure, We can help you. We are very sorry to inform you that, There is no reservation found on Mary Moore. Thank you, For making an inquiry with us regarding change reservation. Have a great day.

USER: Ok, thanks for your wonderful service.