Ripening of blueberries
There may be several reasons for berries not ripening. Even amongst the same groups, different cultivars ripen at different times and some fruits ripen faster than others. You are in good company, this has not been a good year for blueberries. Some gardeners got few berries and Fruit can be variable depending upon the temperatures, maturity, site, and variety of the plants.
Lack of sunlight can be an issue as they grow best in full sunlight but do appreciate some afternoon shade.