Daughters of Ash Havel's quest

[Galkatra]

At final stage of the quest you're supposed to come to Ash Lake. I arrived, saw both Havel, sitting there, and Seath. I didn't know I had to reload the area, so I killed both of them, hoping to get the ring. Yet I only got Havel's weapons, and Seath just keeps respawning near the bonfire. Did I break something?

Everything up until that point was done according to the guide (Had both priscilla's dagger and soul)