Some people find bio made with KOH (potassium)can take a lot longer for the soap to settle, over a week at times.
I suffered just this when I started, then changed to NaOH (sodium) and had clear 50/50 tests in two days (or less) of settling.
The secret to fast settling times is a compleat reaction, if the 27/3 doesn't go instantly clear as opposed to cloudy then clearing over time then you haven't got a compleat reaction.