重启服务器+重启机器后 电力设备全部失效。
[18:13:13] [Server thread/ERROR]: [Slimefun] Failed to properly load this Item
java.lang.NullPointerException: null
        at me.mrCookieSlime.Slimefun.Lists.RecipeType.lambda$static$0(RecipeType.java:44) ~[?:?]
        at me.mrCookieSlime.Slimefun.Lists.RecipeType.register(RecipeType.java:121) ~[?:?]
        at me.mrCookieSlime.Slimefun.Objects.SlimefunItem.SlimefunItem.load(SlimefunItem.java:752) ~[?:?]
        at io.github.thebusybiscuit.slimefun4.implementation.setup.PostSetup.loadItems(PostSetup.java:66) ~[?:?]
        at io.github.thebusybiscuit.slimefun4.implementation.tasks.SlimefunStartupTask.run(SlimefunStartupTask.java:43) ~[?:?]
        at org.bukkit.craftbukkit.v1_16_R3.scheduler.CraftTask.run(CraftTask.java:99) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.craftbukkit.v1_16_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:468) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.MinecraftServer.w(MinecraftServer.java:950) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.MinecraftServer.lambda$a$0(MinecraftServer.java:175) ~[patched_1.16.5.jar:git-Paper-509]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_144]

还有别的报错信息吗
这条看起来是Slimefun的空指针
无法正确加载Slimefun

[18:40:57] [Server thread/ERROR]: Could not pass event EntityDamageByEntityEvent to Slimefun v4.9-dev-210405
java.lang.NullPointerException: null
        at io.github.thebusybiscuit.slimefun4.implementation.listeners.VampireBladeListener.onDamage(VampireBladeListener.java:35) ~[?:?]
        at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor409.execute(Unknown Source) ~[?:?]
        at org.bukkit.plugin.EventExecutor.lambda$create$1(EventExecutor.java:69) ~[patched_1.16.5.jar:git-Paper-509]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:607) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.craftbukkit.v1_16_R3.event.CraftEventFactory.callEvent(CraftEventFactory.java:247) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.craftbukkit.v1_16_R3.event.CraftEventFactory.callEntityDamageEvent(CraftEventFactory.java:1067) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.craftbukkit.v1_16_R3.event.CraftEventFactory.handleEntityDamageEvent(CraftEventFactory.java:954) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.craftbukkit.v1_16_R3.event.CraftEventFactory.handleEntityDamageEvent(CraftEventFactory.java:910) ~[patched_1.16.5.jar:git-Paper-509]
        at org.bukkit.craftbukkit.v1_16_R3.event.CraftEventFactory.handleLivingEntityDamageEvent(CraftEventFactory.java:1099) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.EntityLiving.damageEntity0(EntityLiving.java:1838) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.EntityLiving.damageEntity(EntityLiving.java:1166) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.EntityMonster.damageEntity(EntityMonster.java:52) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.EntityHuman.attack(EntityHuman.java:1113) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.EntityPlayer.attack(EntityPlayer.java:1859) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.PlayerConnection.a(PlayerConnection.java:2251) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.PacketPlayInUseEntity.a(PacketPlayInUseEntity.java:49) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.PacketPlayInUseEntity.a(PacketPlayInUseEntity.java:6) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.PlayerConnectionUtils.lambda$ensureMainThread$1(PlayerConnectionUtils.java:23) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.TickTask.run(SourceFile:18) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.MinecraftServer.bb(MinecraftServer.java:1138) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.MinecraftServer.executeNext(MinecraftServer.java:1131) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.MinecraftServer.sleepForTick(MinecraftServer.java:1092) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.MinecraftServer.w(MinecraftServer.java:1006) ~[patched_1.16.5.jar:git-Paper-509]
        at net.minecraft.server.v1_16_R3.MinecraftServer.lambda$a$0(MinecraftServer.java:175) ~[patched_1.16.5.jar:git-Paper-509]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_144]

一般是插件问题才会报EntityDamageByEntityEvent
有没有出现这个报错的详细原因
如果重启前没问题的话 重启后报错
建议先备份数据 然后清除插件数据试试能否正常使用

它与某个插件裂开了，删掉就好了。奈何两个都是核心插件，所以一直没找出来。