Sourdough stopped rising
I have a starter from King Arthur that I have maintained for about 10 months. I have refreshed it intermittently, with equal parts of AP flour and bottled water, and a 1/2 -1 cup of starter. It then sits at room temp for about 2 hours, and I then refrigerate it, and bring it to room temp before the next feeding. Bubbles form during the rise in temp from the refrigerator, but it BARELY rises, and this has been progressive for about 3 months. The flavor is there, but it seems that the "yeast" part of the starter is gone. Any suggestions?