It depends on your class. Each of the class trees has it's own 'mini-game'/knowledge check. Once you stand on it you press the action button to start it, or if nothings happening then it might be bugged.
Viewing post in In-Game Help/Assistance
I tested all the classes and they work. The only class that doesn't have an interaction with it is the Forlorn. So if you're still a Forlorn then that's the reason. I'll change it now so that in the future it won't show as interactable for Forlorn. If that's not the issue then I'm not sure what it would be. Are you able to stand on that spot? Does it pop up with text when you interact with it?
Yeah, I should probably make it easier since the other 'trials' are pretty easy. I also need to change it so that it'll immediately fail if you press it too early instead of waiting for when the image would've showed. It makes it unclear that you were even supposed to be waiting and just makes it confusing.