Some soft keys won't working but touch is fine

[AC Question]

My lg g3 d851 running on marshmallow suddenly all soft keys other then the back key stop working i replace the button position add new button but nothing happens when i press these button they vibrate but won't perform their functionality afterwards i noticed that notification bar won't work it just scroll down but shows nothing. I try to hard rest but button combination didn't work (volume down +power key) and also screen lock didn't work i try using guest mode but mobile never get locked and also i try using developer tool but in it's menu it just said that this user is not allow to use developer tools