Zombie Pigmen lose name from Name Tag on chunk unload, stack afterwards

[jstnf]

Describe the bug
Some of my players have reported an issue that affects Zombie Pigmen on my Skyblock Server. It seems that, if a chunk is unloaded, and then re-entered, a Pigman loses its custom name from a Name Tag, and then proceeds to stack like a normal, unnamed mob.

To Reproduce
Steps to reproduce the behavior:

• Spawn enough pigmen to trigger a stack, naming each one a different name with Name Tags
• Unload the chunk, and wait for about 30s to 1min
• Re-enter the chunk, and find the pigmen have lost their names, and have stacked

Expected behavior
The Zombie Pigmen should retain their name from a used Name Tag and not stack.

Screenshots/Videos
Will add a video later when I can get on my home computer.

Bukkit/Spigot AND StackMob version:
Paper build 624 (1.13.2)
StackMob v4.0.2
DM me on Discord jstnf#2626 for any other necessary info

Additional context
Pastebin of my config.yml:
https://pastebin.com/NisY1UrK