[Gameplay] Pyke is not getting his HP from items in ARAM

I've happened to luck into Pyke several times lately in ARAM, and I generally build him quite tanky. However I consistently am unable to get the additional HP from items to become actual health. I end up sitting on 1423/2284 or the like. It isn't fixed by buying or selling items, or by death. Occasionally it seems to go up to max, but as soon as you die or buy another item it drops back again. I'm quite confused and frustrated. I would love it dearly if this could be fixed! Thanks!