Twice today my server has crashed with some error message. The message has told me to report to spigot so that's what I'm doing. I have no idea what causes the crash; nothing seems to be going on in console when it happens, and when it crashes, it acts weirdly. Everyone online gets kicked, but the server list itself does not say the server is down. It just endlessly says Pinging. The error message does say that the server, for some reason, stopped responding, which may explain why it acts this way, but I'm really not sure.
I will attach the error message, but I don't know what it means really. I see that you're supposed to post which plugin is causing this issue, but I don't know from the message. The error message mentions a World Generator that I do not have on my server, the plugin ProjectKorra which allows you to have bending like in the Avatar The Last Airbender television series, FactionChat, and some SimplePluginManager that I also have not installed on my server.
I would really appreciate any help anyone could give with this. Thank you