ERROR: Could not pass event PlayerJoinEvent

[Xgabi86]

Stack trace

[17:43:48 ERROR]: Could not pass event PlayerJoinEvent to GrimAC v2.3.72-0763048
java.lang.NullPointerException: Cannot read field "player" because "encoder" is null
        at LightningGrim-bukkit-2.3.72-0763048.jar/ac.grim.grimac.shaded.io.github.retrooper.packetevents.injector.SpigotChannelInjector.isPlayerSet(SpigotChannelInjector.java:62) ~[LightningGrim-bukkit-2.3.72-0763048.jar:?]
        at LightningGrim-bukkit-2.3.72-0763048.jar/ac.grim.grimac.shaded.io.github.retrooper.packetevents.bukkit.InternalBukkitListener.onJoin(InternalBukkitListener.java:87) ~[LightningGrim-bukkit-2.3.72-0763048.jar:?]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[paper-api-1.21.7-R0.1-SNAPSHOT.jar:?]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:71) ~[paper-api-1.21.7-R0.1-SNAPSHOT.jar:?]
        at io.papermc.paper.plugin.manager.PaperEventManager.callEvent(PaperEventManager.java:54) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at io.papermc.paper.plugin.manager.PaperPluginManagerImpl.callEvent(PaperPluginManagerImpl.java:131) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:628) ~[paper-api-1.21.7-R0.1-SNAPSHOT.jar:?]
        at net.minecraft.server.players.PlayerList.placeNewPlayer(PlayerList.java:332) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.network.ServerConfigurationPacketListenerImpl.handleConfigurationFinished(ServerConfigurationPacketListenerImpl.java:184) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.network.protocol.configuration.ServerboundFinishConfigurationPacket.handle(ServerboundFinishConfigurationPacket.java:22) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.network.protocol.configuration.ServerboundFinishConfigurationPacket.handle(ServerboundFinishConfigurationPacket.java:8) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.network.protocol.PacketUtils.lambda$ensureRunningOnSameThread$0(PacketUtils.java:29) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.TickTask.run(TickTask.java:18) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.util.thread.BlockableEventLoop.doRunTask(BlockableEventLoop.java:155) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.util.thread.ReentrantBlockableEventLoop.doRunTask(ReentrantBlockableEventLoop.java:24) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.doRunTask(MinecraftServer.java:1449) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.doRunTask(MinecraftServer.java:176) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.util.thread.BlockableEventLoop.pollTask(BlockableEventLoop.java:129) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.pollTaskInternal(MinecraftServer.java:1429) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.pollTask(MinecraftServer.java:1423) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.util.thread.BlockableEventLoop.managedBlock(BlockableEventLoop.java:139) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.managedBlock(MinecraftServer.java:1380) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.waitUntilNextTick(MinecraftServer.java:1388) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1265) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at net.minecraft.server.MinecraftServer.lambda$spin$2(MinecraftServer.java:310) ~[paper-1.21.7.jar:1.21.7-17-b4466ec]
        at java.base/java.lang.Thread.run(Thread.java:1583) ~[?:?]

How to replicate it if known

Step 1. Start server with plugin
Step 2. Join

Grim version

v2.3.72-0763048

Server version

Paper 1.21.7 - Build 17

Affected Platform(s)

Bukkit

Plugins/mods

[17:51:07 INFO]: ℹ Server Plugins (34):
[17:51:07 INFO]: Paper Plugins (5):
[17:51:07 INFO]:  - FancyDialogs, FancyHolograms, FancyNpcs, HuskHomes, PerfoBooster
[17:51:07 INFO]: Bukkit Plugins (29):
[17:51:07 INFO]:  - AdminCommands, AntiCrasher, AuthMe, AxGraves, AxiomPaper, ChestSort, Chunky, CommandWhitelist, F3NPerm, FastAsyncWorldEdit
[17:51:07 INFO]:  FastLogin, FoxGate, GrimAC, InvSeePlusPlus, LandClaimPlugin, LetUrMemoryRest, LuckPerms, PasiVanish, PlaceholderAPI, ProtocolLib
[17:51:07 INFO]:  SkBee, SkinsRestorer, SkJson, Skript, skript-placeholders, TAB, TradePro, Vault, WorldGuard

[Axionize]

Conflict with Axiom

[Axionize]

Try updating to the latest alpha build (b92). Its not fully fixed but it should be better