Got stuck in one of the game quest (challenge).
Finished the requirement, unable to turn in, the NPC just says his mundane voice line.
No work-around possible. Tried everything and even disabling cloud save then erasing saves files don't work.
Don't want to report an issue because this game breaking bug is known for a long time and nothing seems to be made to fix it.
But at least can you add an option for PC Players to reset "quests" effectively or reset progress in order to allow them to... You know, play the game ?