Asgard's Wrath 2 Seth bossfight bug

During the battle with Seth in Asgard's Wrath 2, after I took off a third of his health and took the maat stone out of the boss's eye, nothing happens, I just stand with the stone in my hands, although Seth should have been freed and the fight should have continued. Restarting the game, the level, and using other characters for combat do not help.