New solar panel not charging battery

Just received a new Ring solar panel and battery.  I charged the battery by the USB cable before installing it in my 3rd gen Stick Up cam.  I connected the panel to the camera, panel is in full sun facing South.  On Ring app, it shows the half sun over the battery with lighting bolt symbol, but the battery is now at 4% causing the camera to go offline.  Earlier this morning, it was at 10%.  Under Solar Status on the Device Health screen, it shows Connected. Why isn't the battery charging?