Abyss not spawn

I’m experiencing a bug related to the Abyss mechanic in Path of Exile 2.

On one of my maps, the Abyss mechanic does not spawn at all, which completely blocks my progression. I have tried running the map multiple times, restarting the game, and recreating the instance, but the issue occurs every time.

Because the mechanic never appears, I am unable to continue the related progression/content/abyss quest line.