I've had the same issue on my S5. When I go to the permissions screen, it won't let me change the setting. Another poster here indicated the problem lies in the DU battery/booster apps. I uninstalled both and *so far* I can now use the apps that formerly generated the error messages. Good luck!
You may have to go into "Safe-Mode". Hold Power Key, once prompted to shutdown/restart/etc. Press and hold shutdown, it will prompt for you to reboot into "Safe-Mode". Once pressed and booted into safe mode, go to settings and application manager. You may have to disable all google and Verizon, my Verizon permissions. you may have to click the triple stacked colon in the top right-hand corner of the screen and go to show system apps, etc. Once a particular app is selected you will find yourself at screen in which it will ask to Force Stop or Disable; below you will find a permissions area or tab. Press to enter. turn off all permissions you feel apply.
You may have to laboriously do this to all apps and then systematically enable apps that you have just disabled to bring continuity back to other apps. Also check the "Draw over other applications" tab.
Being that Verizon is our Carrier, I would suggest keeping pertinent services added or permissions granted, thus by isolating this factor if your problem persists, you can then show focus to Verizon Agents when troubleshooting; going forward.
At last, make certain to check the permissions of the app-in-particular for the standing permissions. Either first or in the entirety of your device functionality settings.
Unfortunately, it is an age ruled by savvy and 'youthful' purveyors, but "in-general" the whole android experience is organic and "open-source" so changes are at constant. Admittedly, I think some aspects are invasive and controlling, but... So if you desire to keep the new and best, as the trends come week to week as it seems. It would behoove you to play with your device and change this or that and see what happens. Usually and in general, nothing you can do can destroy or corrupt your device beyond general use.
***CAVEAT***-However it is a maze of protocol and permissions to set everything back to "Standard" in the sense of losing sight of what you have granted and what you have restricted; as some restrictions/permissions can affect the performance or greater capacity of applications of use and interest.