Also, make sure to check your settings in AOD to see if you're AOD is set to show only when new notifications come in because if it's set to that, you won't see AOD until you get a notification. I saw that mine happened to be set on that.
Found the root cause. When apps such as Naptime turn on power saving mode when the screen is off, the AOD preference in the power saving mode settings is not being respected.
