You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Please change my existing reservation due to some health issues?

ASSISTANT: I am sorry to hear that. I will help you. Please help me with your name.

USER: Sure, I am Kevin Lee.

ASSISTANT: Please allow me a minute.

USER: Sure.

ASSISTANT: Kevin Lee, I am really sorry to inform you that there is no booking done on your name to make the changes as per your request.

USER: Ok, not an issue.

ASSISTANT: Thank you for understanding.

USER: Thank you for your information.