How to use negation in text?

[abhishakskilrock (Abhishak Varshney)]

Hi,

I want to use negation in my bot.

e.g.

User: I want to know about you.

Bot: I am a rasa-bot. I like to chat.

User: I don't want to know about you.

Bot: Okay, No Problem. I am here to help you.

Anyone knows how can I do that?