You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

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

ASSISTANT: Sure, may I know your name?

USER: I am Nicholas Perez.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry to say, no reservation found with your name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thanks for reaching us.