you must high speed internet. closed contect and go to setting-account-google, sync it all and keep it some time, then open contact again if you see contact show , you go to home-tool folder- backup your phone(don't close you contact). wait until finish. after finish you go to setting-reset your phone (don't tick earas data). than restore from your last back up but decline all google service when it asking. after go setting-account if have google remove it.