Trying to run a fabric Minecraft modpack but i keep getting error "root tag must be named compound tag"

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OS Name/Version: windows 10 (server)

Problem Description: i get an error “root tag must be named compound tag” every time i try to connect to the server
i installed the big chad guy modpack(non cobblemon) and was playing on aternos with some friends. it isn’t very powerful so i decided to host. but after installing the provided server files from BCG+ and putting fabric with the right version but the error keeps persisting i just wanna play with my friends.

Actions taken to resolve so far:
i have tried vanilla and fabric standalone(no mods) and it works fine
i have tried reinstalling the server file it didn’t change anything
i have try joining the server with an no mods (client side) and i was able to connect
i deleting the instance and remaking it didn’t change anything
i have looked online but can’t find anything to fix my problem

the client logs:
io.netty.handler.codec.DecoderException: io.netty.handler.codec.EncoderException: java.io.IOException: Root tag must be a named compound tag

at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:489) ~[netty-codec-4.1.82.Final.jar:?]

at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:280) ~[netty-codec-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:336) ~[netty-codec-4.1.82.Final.jar:?]

at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:308) ~[netty-codec-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:336) ~[netty-codec-4.1.82.Final.jar:?]

at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:308) ~[netty-codec-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103) ~[netty-codec-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:286) ~[netty-handler-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:788) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:724) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:650) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:562) ~[netty-transport-4.1.82.Final.jar:?]

at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997) ~[netty-common-4.1.82.Final.jar:?]

at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.82.Final.jar:?]

at java.lang.Thread.run(Thread.java:833) ~[?:?]

Caused by: io.netty.handler.codec.EncoderException: java.io.IOException: Root tag must be a named compound tag

serveur side log:
RedJives joined the game

RedJives lost connection: Disconnected

RedJives left the game

i appreciate any help thank you.

It might be down to some trial+error to figure out what mod(s) are causing the issue.
Also double check that you have the Server Jar set to fabric.jar

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