You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change my existing reservation, can you please help me with this?

ASSISTANT: Sure, I am here to help you. May I know your good name?

USER: I am Katherine Brown.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for your time, No reservation was found on your given name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for choosing us.