I have the same problem and I have checked my setting and my "Restrict background data" is unchecked and my "Auto-sync data" is checked as it should be. Still I cannot use Google Play Store.
The settings link I posted works with the many phones I have used or using now. Recheck all of your settings and if all are correct you should be able to connect to Google Play store settings. On some devices the setting are listed or hidden under other data options. If still not working then go into all apps and do a force stop on Google play store, clear cache & data, turn off and uninstall the app. Restart phone and reinstall app again and go to play store as normal.