You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, welcome to flight booking agency. How can I guide you for today?

USER: My name is Jonathan Lee. I want to cancel my reservation, because I got to know that the service of Delta airline is not good. Can you help me?

ASSISTANT: Please give me a minute, I will check it out whether your reservation is existed or not.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: That's fine, thanks for your help.

ASSISTANT: You are welcome. Thank you for approaching us.