I have error in console

[Savranchuk]

https://mclo.gs/o7Hono5

Purpur 1.21.4

Strange error appearing in console

[Ajneb97]

Make sure you are using the latest version of ProtocolLib that supports 1.21.4

[ToxykAuBleu]

Same kind of errors, see version of plugins and server at bottom of logs:

[20:29:36] [Netty Epoll Server IO #3/ERROR]: [EasyCommandBlocker] Unhandled exception number 131072 occurred in onPacketReceiving(PacketEvent) for EasyCommandBlocker
java.lang.IllegalStateException: Unable to read field value of private final java.lang.String net.minecraft.network.protocol.game.ServerboundCommandSuggestionPacket.command
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.reflect.accessors.DefaultFieldAccessor.get(DefaultFieldAccessor.java:30) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.reflect.StructureModifier.readInternal(StructureModifier.java:302) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.reflect.StructureModifier.read(StructureModifier.java:253) ~[ProtocolLib-v5.3.0.jar:?]
        at EasyCommandBlocker.jar/ecb.ajneb97.spigot.managers.ProtocolLibManager$1.onPacketReceiving(ProtocolLibManager.java:56) ~[EasyCommandBlocker.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.collection.InboundPacketListenerSet.invokeListener(InboundPacketListenerSet.java:25) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.collection.PacketListenerSet.lambda$invoke$0(PacketListenerSet.java:123) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.timing.TimingTracker.lambda$static$0(TimingTracker.java:7) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.collection.PacketListenerSet.invoke(PacketListenerSet.java:123) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.collection.PacketListenerSet.invoke(PacketListenerSet.java:102) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.PacketFilterManager.postPacketToListeners(PacketFilterManager.java:528) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.PacketFilterManager.invokeInboundPacketListeners(PacketFilterManager.java:509) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.netty.channel.NettyChannelInjector.processInboundInternal(NettyChannelInjector.java:455) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.netty.channel.NettyChannelInjector.processInbound(NettyChannelInjector.java:439) ~[ProtocolLib-v5.3.0.jar:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.netty.channel.InboundPacketInterceptor.channelRead(InboundPacketInterceptor.java:47) ~[ProtocolLib-v5.3.0.jar:?]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:346) ~[netty-codec-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:318) ~[netty-codec-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.injector.netty.channel.InboundProtocolReader.channelRead(InboundProtocolReader.java:25) ~[ProtocolLib-v5.3.0.jar:?]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.handler.flow.FlowControlHandler.dequeue(FlowControlHandler.java:202) ~[netty-handler-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.handler.flow.FlowControlHandler.channelRead(FlowControlHandler.java:164) ~[netty-handler-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:442) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:107) ~[netty-codec-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.115.Final.jar:4.1.115.Final]
        at ViaVersion-5.2.1.jar/com.viaversion.viaversion.connection.UserConnectionImpl.fireChannelRead(UserConnectionImpl.java:280) ~[ViaVersion-5.2.1.jar:?]
        at ViaVersion-5.2.1.jar/com.viaversion.viaversion.connection.UserConnectionImpl.sendRawPacketToServerServerSide(UserConnectionImpl.java:263) ~[ViaVersion-5.2.1.jar:?]
        at ViaVersion-5.2.1.jar/com.viaversion.viaversion.connection.UserConnectionImpl.sendRawPacketToServer(UserConnectionImpl.java:234) ~[ViaVersion-5.2.1.jar:?]
        at ViaVersion-5.2.1.jar/com.viaversion.viaversion.protocol.packet.PacketWrapperImpl.sendToServer0(PacketWrapperImpl.java:502) ~[ViaVersion-5.2.1.jar:?]
        at ViaVersion-5.2.1.jar/com.viaversion.viaversion.protocol.packet.PacketWrapperImpl.sendToServer(PacketWrapperImpl.java:485) ~[ViaVersion-5.2.1.jar:?]
        at ViaVersion-5.2.1.jar/com.viaversion.viaversion.api.protocol.packet.PacketWrapper.sendToServer(PacketWrapper.java:358) ~[ViaVersion-5.2.1.jar:?]
        at ViaBackwards-5.2.1.jar/com.viaversion.viabackwards.protocol.v1_21_2to1_21.task.PlayerPacketsTickTask.lambda$run$0(PlayerPacketsTickTask.java:58) ~[ViaBackwards-5.2.1.jar:?]
        at io.netty.util.concurrent.PromiseTask.runTask(PromiseTask.java:98) ~[netty-common-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.util.concurrent.PromiseTask.run(PromiseTask.java:106) ~[netty-common-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.util.concurrent.AbstractEventExecutor.runTask(AbstractEventExecutor.java:173) ~[netty-common-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:166) ~[netty-common-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:472) ~[netty-common-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:405) ~[netty-transport-classes-epoll-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997) ~[netty-common-4.1.115.Final.jar:4.1.115.Final]
        at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.115.Final.jar:4.1.115.Final]
        at java.base/java.lang.Thread.run(Thread.java:1583) ~[?:?]
Caused by: java.lang.ClassCastException: Cannot cast net.minecraft.network.protocol.game.ServerboundClientTickEndPacket to net.minecraft.network.protocol.game.ServerboundCommandSuggestionPacket
        at java.base/java.lang.Class.cast(Class.java:4067) ~[?:?]
        at ProtocolLib-v5.3.0.jar/com.comphenix.protocol.reflect.accessors.DefaultFieldAccessor.get(DefaultFieldAccessor.java:28) ~[ProtocolLib-v5.3.0.jar:?]
        ... 50 more
/ver EasyCommandBlocker
[20:32:28] [Server thread/INFO]: EasyCommandBlocker version 1.12.1
[20:32:28] [Server thread/INFO]: Author: Ajneb97
/ver ProtocolLib
[20:33:10] [Server thread/INFO]: ProtocolLib version 5.3.0
[20:33:10] [Server thread/INFO]: Provides read/write access to the Minecraft protocol.
[20:33:10] [Server thread/INFO]: Authors: dmulloy2 and comphenix
/ver
[20:36:40] [Thread-63/INFO]: This server is running Paper version 1.21.4-151-main@9b9de82 (2025-02-15T11:49:01Z) (Implementing API version 1.21.4-R0.1-SNAPSHOT)

[Ajneb97]

Use ProtocolLib 5.4.0: https://ci.dmulloy2.net/job/ProtocolLib/

[ToxykAuBleu]

Sorry for the late answer 😅
On my side, this fixes the problem. Thanks 👍