Plug in dev issues

I'm currently trying to develop a plugin for Minecraft 1.16.5 that works with economy plugins like essentialsX with vault and I'm having an issue getting it to actually load up in my server if anyone with the knowledge and skills is willing to take a look and maybe see if you can figure it out that would be awesome. i have verry little knowledge in this stuff so I'm not surprised that its not working. any help would be appreciated.