You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Jack Robinson here.

ASSISTANT: How can I help you Jack?

USER: I need to cancel my recent reservation because my health condition was not good.

ASSISTANT: Sure, I am at your service to help you. Please wait for a moment.

USER: Sure, take your own time.

ASSISTANT: Sorry Jack, no reservation found under your name.

USER: It's ok, not a problem.Thank you for checking.

ASSISTANT: Thank you.