EncoderException : java.lang.NullPointerException @ io.netty.handler.codec.MessageToByteEncoder:125
io.netty.handler.codec.EncoderException: java.lang.NullPointerException
at io.netty.handler.codec.MessageToByteEncoder.write(MessageToByteEncoder.java:125) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:717) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.channel.AbstractChannelHandlerContext.invokeWriteAndFlush(AbstractChannelHandlerContext.java:764) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.channel.AbstractChannelHandlerContext$WriteTask.run(AbstractChannelHandlerContext.java:1071) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:164) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:472) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:384) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[BungeeCord.jar:git:Waterfall-Bootstrap:1.15-SNAPSHOT:e45fb1f:340]
at java.lang.Thread.run(Thread.java:832) [?:?]
Caused by: java.lang.NullPointerException
What's happening there?