Warm weather is what happened. Most of mine just quit when it hit 60 here. With these colds nights coming they'll reset, and sap will be back. Your on the same latitude as I am in southern Ohio, I'm guessing your season is about over is part of it too. I figure my last boil will be Monday (3/8/21) and Tuesday I'll drain and finish off my sweet and call it a season. They'll be some sap after that, but temps in the 60s will make a funky mess of everything so I'm quitting before that happens.
125-150 taps
Smokey Lakes Full pint Hybrid pan
Modified half pint arch
Air over fire
All 3/16 tubing
Southern Ohio