How to troubleshoot/debug slow phone that burns battery?
Educated guess is you have apps that are running in the background and eating up your battery. Samsung power manager app/thing is not great (at least on my sgs7 it isn't), but it's pointing you on possible culprits. Easiest way to debug is uninstall the apps and see if device acts any differently (give it a few days or a week to see). Or another way is factory reset start from new and see how it goes from "stock" and add apps slowly and see. Or it could just be the battery is aging and simply can't hold a charge like it used to. There isn't a silver bullet way of trouble shoot battery life unfortunately.