Mana Blessing doesn't work

I just allocated Mana blessing on my amulet through instillment.
My mana before was 6222. After instillment it's still 6222, not only I didn't get 5%, but 20 extra mana doesn't work too. It's a little silly, that even simple instillment doesn't work

Same for me ... the stats don't change

+1, the instill seems to only add +13 mana when I used it. Which isn't even the +20 it said let alone the 5% max