I couldn't get the 6th Map Boss Atlas point, I've tried everything

Hi everyone,
I’ve been struggling non-stop for seven straight hours and nothing seemed to work.
I ran 10 Tier 15 (both rare and corrupted) maps with 3 notes: Map Boss, Irradiated, Corrupted and so far no Boss Atlas points gained. Before that I got 4 points from defeating Map Boss at area lvl 79 & 80 quite easily, but that's all Ive got until now.

Am I doing something wrong? Please help!