Shattered and Lost Not Progressing

Riswa

Killed the Lost One 3 times quest still says find and defeat the Lost One. Can find nothing on the forum other than it used to be a problem. Come on Bethesda fix something! I shut down my PS4 and came back and same thing BUGGED. Its a tough fight so it is annoying that it is broken and I will not be informed of the fix so I randomly need to check back or read the voluminous update notes for a month. COME ON MAN