Hi there, @Sebastian_Frey 
At the moment, this functionality isn’t supported in our app, but we have a bunch of requests that are related to this issue. Feel free to upvote them here:
While we unfortunately can’t block real people from abusing the widget, we’ve got a solution that blocks bots from using your AI Chatbot. This article explains how you can do this 
- How to stop bot spam in your AI Chatbot