Localized language settings are invalid

[lelmc]

Nucleus Version

3.0.0-BETA3

Sponge Version

spongeforge-1.16.5-36.2.5-8.1.0-RC1141

Java Version

java8

Plugins/Mods

ForgePlaceholderAPI-Forge-2.0.4-1.16.5.jar
griefdefender-spongeforge-api8-2.1.7-TEST1.jar
LuckPerms-Sponge-5.4.25.jar
Nucleus-3.0.0-BETA3-MC1.16.5-SpongeAPI8.1-plugin.jar
Pixelmon-1.16.5-9.0.1-server.jar

Describe the bug

Tried restarting after setting override-language=zh-CN in core_config.conf, the language did not change anything

output in the console：
[22:44:28] [Server thread/INFO] [nucleus/]: Using default flat file storage for user data.
[22:44:28] [Server thread/INFO] [nucleus/]: Using default flat file storage for world data.
[22:44:28] [Server thread/INFO] [nucleus/]: Using default flat file storage for general data.
[22:44:28] [Server thread/INFO] [nucleus/]: Nucleus language set to "zh-CN"