2 different server instances, 2 different modpacks (Both running latest Forge 1.16.5-36.1.31), both are spamming the log with errors:

Server 1:

Spoiler

[14Jun2021 15:32:52.844] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/PhoenixsAssortedGoodies/config/topaddons-common.toml is not correct. Correcting
[14Jun2021 15:33:02.848] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/PhoenixsAssortedGoodies/config/dtnaturesaura-common.toml is not correct. Correcting
[14Jun2021 15:33:02.850] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/PhoenixsAssortedGoodies/config/topaddons-common.toml is not correct. Correcting
[14Jun2021 15:33:12.845] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/PhoenixsAssortedGoodies/config/dtnaturesaura-common.toml is not correct. Correcting
[14Jun2021 15:33:12.847] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/PhoenixsAssortedGoodies/config/topaddons-common.toml is not correct. Correcting
[14Jun2021 15:33:22.870] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/PhoenixsAssortedGoodies/config/dtnaturesaura-common.toml is not correct. Correcting

Server 2:

Spoiler

[14Jun2021 15:30:35.633] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/KimchinkSink/config/capsule-common.toml is not correct. Correcting
[14Jun2021 15:30:45.644] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/KimchinkSink/config/capsule-common.toml is not correct. Correcting
[14Jun2021 15:30:55.633] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/KimchinkSink/config/capsule-common.toml is not correct. Correcting
[14Jun2021 15:31:05.669] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/KimchinkSink/config/capsule-common.toml is not correct. Correcting
[14Jun2021 15:31:15.632] [Thread-0/WARN] [net.minecraftforge.fml.config.ConfigFileTypeHandler/CONFIG]: Configuration file /var/games/minecraft/servers/KimchinkSink/config/capsule-common.toml is not correct. Correcting

Every 10 seconds, I get these messages. Deleting the file in question doesn't help, the files appear to be correct toml, and besides, are the defaults created by the mod/forge.

It's not a permissions error with the file or folder (Files are being created, as are backups:

Spoiler

-rw-r--r--   1 mcserver  mcserver    208 Jun 13 15:17 thermal-client.toml
-rw-r--r--   1 mcserver  mcserver   1348 Jun 13 15:17 toastcontrol-common.toml
-rw-r--r--   1 mcserver  mcserver   1589 Jun 13 15:17 topaddons-client.toml
-rw-r--r--   1 mcserver  mcserver    430 Jun 14 15:39 topaddons-common-1.toml.bak
-rw-r--r--   1 mcserver  mcserver    430 Jun 14 15:39 topaddons-common-2.toml.bak
-rw-r--r--   1 mcserver  mcserver    430 Jun 14 15:39 topaddons-common-3.toml.bak
-rw-r--r--   1 mcserver  mcserver    430 Jun 14 15:39 topaddons-common-4.toml.bak
-rw-r--r--   1 mcserver  mcserver    430 Jun 14 15:39 topaddons-common-5.toml.bak
-rw-r--r--   1 mcserver  mcserver    430 Jun 14 15:39 topaddons-common.toml
-rw-r--r--   1 mcserver  mcserver   2445 Jun 13 19:39 torchmaster.toml

 

And the files and their backups are identical), so at this point I am at a loss as to what's causing it.

Server is running on FreeBSD 12, with Java version 11.0.10:

openjdk 11.0.10 2021-01-19
OpenJDK Runtime Environment (build 11.0.10+9-1)
OpenJDK 64-Bit Server VM (build 11.0.10+9-1, mixed mode)

Nothing at all?