Level 82 Abyssal Depth not giving Challenge reward (Settlers)

I am working on Unbelievable Undertakings in Settlers League. This has happened twice where I complete an Abyssal Depth >= Level 81 and do not get the reward. The state of this specific challenge is currently:

* Abyssal Depths (4/5) 
* Tier 4 Harvest Seeds (COMPLETE)
* Blighted or Blight Ravaged Maps (COMPLETE)
* All Rituals in a Map with at Least one Blood-filled Vessel applied. (COMPLETE)
* Domains of Timeless Conflict with at least 25 rewards (1/3)

The first time it happened was in a level 81 area, so I thought maybe the >= level 81 was wrong, or I was wrong. So, I used a map where the monster level was 82. I was using Abyss Scarabs in these maps, to help find the Abyssal Depths.

I should have been awarded the the Challenge Unbelievable Undertakings and I do not. It still says (4/5) after I kill the boss and all enemies in that Abyssal Depth.

Just now, I got the Challenge Reward by completing an Abyssal Depth somewhere that was Monster Level 83 (Ashen Wood). I was not using an Abyss Scarab this time.