You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Katherine Wright here. I want to change my existing reservation due to my board exams. So please help me in this one.

ASSISTANT: Sure, I am here to help you with this. Sorry Katherine, there is no reservation found as per your name to change it.

USER: No issues, thank you for your response.

ASSISTANT: You are welcome.