Fortify implicit does not refresh fortification buffs

When I attack with fortify-support gem, the current fortify buff stack is refreshed. For example I had 5 Stacks and get 3 new Stacks, then I have 8 stacks that all end together in some seconds.

But if I attack with my implicit corupted "melee hits have chance to fortify" on mace, there is no refresh. If i had 5 Stacks and get 3 new Stacks, I have 8 stacks, but the 5 Stacks will run out earlier than the 3.