Skywars Plugin ERROR

Sorry, there has been an error!

ID: 3d3f4f8169c79d6e-AMS
Error: 504

Plugin Link;https://aternos.org/plugins/p/28268

I tried to install plugin serverime but it did not work but I installed it again then restarted the server I got the file called plugins in the file named files How to make the jars inside the file that writes plugins?

I am installing the plugin If the aternos / filese plugin comes in its own folder, how do I load the classic stuff called plugins in aternos / filename