You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Owing to an emergency, I want to cancel my recent reservation. Can you please help me in that?

ASSISTANT: Sure, I will help you in flight ticket cancellation.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Myself David Perez.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: Thanks for waiting.

USER: Ok.

ASSISTANT: Sorry there is no flight reservation to cancel it.

USER: Ok, no problem.

ASSISTANT: Thank you.

USER: Thank you for your information.