You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Charles Walker. Owing to an emergency, I want to cancel my reservation, so please help me in the cancellation.

ASSISTANT: Sure. Please wait for a moment.

USER: Ok.

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

USER: Not an issue. Thank you.

ASSISTANT: Thank you.