You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today from my end?

USER: I am Katherine Carter. I am planning to cancel my recent reservation, due to health issue. Can you please change my ticket?

ASSISTANT: Sure, I am gleeful to help you out. Please allow me a moment to check whether any reservation on your name to modify it.

USER: Sure.

ASSISTANT: Sorry Katherine Carter, there is no active reservation on your name to change it.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you for reaching us.