Hi,
This update fixes an incompatibility with Paper. They rewrote the commands system, so it required a different implementation than for spigot.
In order to keep the code clean (otherwise you would have code for both spigot and paper even if you only use one), you should now install the commandAPI plugin (spigot or paper version), available here:
https://docs.commandapi.dev/user-setup/install
If that is too complicated, let me know and I will either create two versions of Oraxen or include both codes in the plugin.
As always, enjoy the weekend,
Thomas