You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: Owing to an emergency, my appointment with doctor got cancelled. So I want you to cancel my existing reservation.

ASSISTANT: Sure, I will help you with the cancellation of flight reservation. Please wait for a moment.

USER: Sure.

ASSISTANT: May I know your name please.

USER: Sure, Katherine Thompson here.

ASSISTANT: I have searched online but I could not find your flight reservation to cancel it.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you.