Fangs of Frost Quality

Wanted to use Fangs of Frost for the Quality bonus of "X% chance to not consume Parry Debuff" but it seems to just not work at all. Right now I have a 16% chance to not consume the debuff, Ran around the map didnt see it proc then fought The Mastodon Badlands bosses and between fighting both of them I didnt see it happen a single time either. Seems like it does absolutely nothing at the momoent and that kinda sucks