I've killed Octav the Firebrand twice, have two of his teeth, and cannot complete the bounty

[Neminan]

Somehow by accident I fought Octav and his team twice, I know have two of his teeth, and cannot complete the quest.
Is there a way to drop one of his trophy's?

[SeaSquall]

I have the exact  same issue, but its with Tempestuous Luandi instead.  

Same issue, she spawned again so I killed her again and I have 2 of her bounty item in my inventory and I can't turn in the bounty.

[Rhankala]

Same for me. I encountered and killed Octav twice all before getting into the city and accepting his bounty, I have 2 of his teeth, but I can't turn the quest in. I killed two other bounty targets before accepting their quests but I was able to turn those in just fine. I'm playing on Xbox series X. The game is up to date.