[23:49:43 INFO]: Mardaster issued server command: /clans
[23:49:43 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'clans' in plugin UltimateClans v8.2.1
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:47) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:159) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
        at org.bukkit.craftbukkit.v1_18_R2.CraftServer.dispatchCommand(CraftServer.java:906) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.server.network.ServerGamePacketListenerImpl.handleCommand(ServerGamePacketListenerImpl.java:2307) ~[?:?]
        at net.minecraft.server.network.ServerGamePacketListenerImpl.handleChat(ServerGamePacketListenerImpl.java:2118) ~[?:?]
        at net.minecraft.server.network.ServerGamePacketListenerImpl.handleChat(ServerGamePacketListenerImpl.java:2099) ~[?:?]
        at net.minecraft.network.protocol.game.ServerboundChatPacket.handle(ServerboundChatPacket.java:46) ~[?:?]
        at net.minecraft.network.protocol.game.ServerboundChatPacket.a(ServerboundChatPacket.java:6) ~[?:?]
        at net.minecraft.network.protocol.PacketUtils.lambda$ensureRunningOnSameThread$1(PacketUtils.java:51) ~[?:?]
        at net.minecraft.server.TickTask.run(TickTask.java:18) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.util.thread.BlockableEventLoop.doRunTask(BlockableEventLoop.java:153) ~[?:?]
        at net.minecraft.util.thread.ReentrantBlockableEventLoop.doRunTask(ReentrantBlockableEventLoop.java:24) ~[?:?]
        at net.minecraft.server.MinecraftServer.doRunTask(MinecraftServer.java:1400) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.server.MinecraftServer.d(MinecraftServer.java:188) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.util.thread.BlockableEventLoop.pollTask(BlockableEventLoop.java:126) ~[?:?]
        at net.minecraft.server.MinecraftServer.pollTaskInternal(MinecraftServer.java:1377) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.server.MinecraftServer.pollTask(MinecraftServer.java:1370) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.util.thread.BlockableEventLoop.runAllTasks(BlockableEventLoop.java:114) ~[?:?]
        at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1504) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1226) ~[paper-1.18.2.jar:git-Paper-388]
        at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:316) ~[paper-1.18.2.jar:git-Paper-388]
        at java.lang.Thread.run(Thread.java:1583) ~[?:?]
Caused by: java.lang.NoSuchFieldError: Class org.bukkit.inventory.ItemFlag does not have member field 'org.bukkit.inventory.ItemFlag HIDE_ARMOR_TRIM'
        at me.ulrich.clans.manager.uVwX2y.aB2cD3(Unknown Source) ~[UltimateClans-8.2.1.jar:?]
        at me.ulrich.clans.manager.eFgH5.xYzA2.eFgH5(Unknown Source) ~[UltimateClans-8.2.1.jar:?]
        at me.ulrich.clans.aB2cD3.eFgH5.noArgs(Unknown Source) ~[UltimateClans-8.2.1.jar:?]
        at me.ulrich.clans.interfaces.CommandHandler.onCommand(Unknown Source) ~[UltimateClans-8.2.1.jar:?]
        at me.ulrich.clans.aB2cD3.eFgH5.onCommand(Unknown Source) ~[UltimateClans-8.2.1.jar:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:45) ~[paper-api-1.18.2-R0.1-SNAPSHOT.jar:?]
        ... 21 more