Flashlight icon on iPhone 11 lockscreen is "dead"

At the bottom corners of the lock screen on my iPhone 11 (IOS 13.2.3) there are two icons, a flashlight and a camera. Tapping the camera icon in the right bottom corner does open the camera, but the flashlight icon in the left bottom corner is "dead." Nothing happens when I tap it, although when I tap that icon in the Control Center I can toggle the flashlight on and off. Why might the lock screen flashlight icon be inoperative?