Hextech Chests never drop

So since the hextech crafting was released, so far i've only gotten 2 chests (excluding the free one). I don't know if there's anyone else facing the same problem but the hextech chests never seem to drop. Since i'm a 1 trick i get an S rank in about 50% of the games, but i never seem to drop any chests, regardless of whether i'm playing solo, duo, or even with 4 other premades. The Chests are supposedly easier to drop than keys, but even though i've got 4 chests available all the time i can't seem to get any for my games.