You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I would like to change my existing reservation, which is done recently. Can you please help me out?

ASSISTANT: Sure, we are here to help you.

USER: Thank you for considering my request.

ASSISTANT: May I know your name please?

USER: Sure, myself Kenneth Roberts.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: Not an issue, anyway thank you for the information.

ASSISTANT: Thank you for contacting us.