You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Can you please help me to change my existing reservation?

ASSISTANT: Sure, I am here to help you with that, can I know your good name to proceed further?

USER: Myself Gary Parker.

ASSISTANT: Sorry, we found no reservation on your given name.

USER: Ok, not an issue. Thank you for checking.

ASSISTANT: Thank you for reaching us.