There's many problems, i will update the review until all problems are solved:

1) Conventions: By java conventions, ALL classes must have it's name in "Uppercase"... Example: "fileLoading.java" must be "FileLoading.java"

2) Command labels: your command labels are way too generic, you can't name your command /reloadconfig, because it's ambiguos

3) Hardcoded messages: All the messages for changing gamemode are hardcoded, i can't modify it by config

4) In the "chageGamemode" you use... multiple if statement inside a default case of a switch??? why??? that's not how a switch statement works

5) Try to avoid console printing using "System.out.println()", instead use: PluginInstance.getLogger().info("message here");


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I'm not insulting you or your plugin, i just want to help you write better