HELP - LG G3 F400K ask for phone PIN!

Hi, i have a friend who have the F400K Korean version of G3 and he have a problem...i dont know what he doing to the phone but now the phone are in the menu with korean language, the only thing they say in my understanding language is PIN word in the top.

i think is the phone get locked but dont know what to solve this, is a phone lock not a network lock...

anyone can help?

thanks