y wont bagarn enable wriath guard

[Darchonis]

i have both the books, his journal and plans, and i talked to

bagarn. he said to return in 1 day, so i did. he said that he has

learned all he can and if im still willing he will enable it so i click on

it and it never works. he keeps repeating himself. if i drop the

wraithguard on the ground he says he cant do it because i dont

have it. someone plz help me.