Cannot find specific plugin

I wanted to add this plugin to my server: https://www.spigotmc.org/resou…onfig-1-8-x-1-16-5.74292/
It says that the plugin has already been added, but I cannot find it anywhere in the mods section to add it.

Can someone help me find the plugin?

Quote from ItzzMic

Here you go: https://aternos.org/addons/a/spigot/74292

Thanks for the help, but...

Yes, that was the problem, but I had to reinstall my world for that. When I created the backup and uploaded it, it deleted the spiggot pluggin.