Originally Posted by sydvikki
no reply = no solution. . .
Download Short cut Master Lite App (in Play Store). Open it N go to App Explorer in menu. Scroll down to com.lge.hiddenmenu, click on that. it gives u a sub menu, u tape on settings, u will see update touch firmware, click on that n wait few second before re booting ur phone et voilà Knock code is back.