Not enough info, maybe bad brand or dosage. Maybe you have other immune issues. Not well known but there are people who simply can not absorb D thru the gut.

Not enough info, maybe bad brand or dosage. Maybe you have other immune issues. Not well known but there are people who simply can not absorb D thru the gut. A high school friend is one. Shouldn’t discourage the 90%+ who can benefit because of exceptions.