Share 'Astringency'

I encountered with something very weird during conching (Is it?). I roast this set of beans, and it smells so nice, during the first 3 hours I was able to pull off all of the acids, and I added in refined sugar, at that time I really love the taste, but everything is coarse, so I let it conch over night, the next morning the chocolate was smooth but with astringent taste and smell. Where does it…