You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am  Carolyn Gonzalez want to change my reservation due to postpone of my meeting.

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, we have not found any flight reservation on your given name.

USER: Ok, thank you for your information.

ASSISTANT: Thanks for choosing us.