I have a Samsung S5. My backup setting is enabled. My Gallery app sync settings have Sync Google+ Photos enabled. It says last synced few hours ago. Everything is set to backup/sync to the same gmail account (note haven't changed any of these settings for as long as I can remember). But, if I go to Google Photos, there aren't any photos there in the last 2 years. When I go to Google+, I don't seen any menu item for photos.
I can't tell if they aren't actually syncing or I'm looking for them in the wrong place.