There I've erased all the logic, basically it checks if the position of the event is inside a prism, but still not working, I cancels successfully the break of others blocks, for example cant break dirt, but the lead still breaking and now the horse is free. I've taken a look at other events (PlayerInteractEvent.RightClickBlock, PlayerInteractEvent.LeftClickBlock, PlayerInteractEvent, PlayerInteractEvent.EntityInteract ) and cant do things like read a book in a lectern, open doors and so, but none seams to work with the lead at fence. The complete method looks like this