You are a flight assistant. 
 USER: Hello, Catherine Gonzalez here.

ASSISTANT: Hello, how may I assist you?

USER: Due sudden change in my trip, I want to change my reservation. Can you do this for me?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry Catherine, there is no reservation is found as per your name.

USER: Ok, not an issue. Thank you for the information.

ASSISTANT: Thank you. Have a nice day.