Hỏi đáp Lỗi của ShopGUIPlus

[20:45:56 ERROR]: Could not pass event InventoryClickEvent to ShopGUIPlus v1.49.0
java.lang.NoClassDefFoundError: net.mmogroup.mmolib.api.item.NBTItem
at net.brcdev.shopgui.provider.item.MMOItemsItemProvider.isValidItem(MMOItemsItemProvider.java:24) ~[?:?]
at net.brcdev.shopgui.item.ItemManager.lambda$getCustomItemProvider$1(ItemManager.java:77) ~[?:?]
at java.util.stream.ReferencePipeline$2$1.accept(Unknown Source) ~[?:?]
at java.util.ArrayList$ArrayListSpliterator.tryAdvance(Unknown Source) ~[?:?]
at java.util.stream.ReferencePipeline.forEachWithCancel(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.copyIntoWithCancel(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.copyInto(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.wrapAndCopyInto(Unknown Source) ~[?:?]
at java.util.stream.FindOps$FindOp.evaluateSequential(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.evaluate(Unknown Source) ~[?:?]
at java.util.stream.ReferencePipeline.findFirst(Unknown Source) ~[?:?]
at net.brcdev.shopgui.item.ItemManager.getCustomItemProvider(ItemManager.java:77) ~[?:?]
at net.brcdev.shopgui.util.ItemUtils.compareItemStacks(ItemUtils.java:555) ~[?:?]
at net.brcdev.shopgui.config.Settings.getMaxStackSize(Settings.java:416) ~[?:?]
at net.brcdev.shopgui.shop.ShopItem.getMaxStackSize(ShopItem.java:433) ~[?:?]
at net.brcdev.shopgui.gui.gui.AmountSelectionGui.getMaxStackSize(AmountSelectionGui.java:260) ~[?:?]
at net.brcdev.shopgui.gui.gui.AmountSelectionGui.handleAmountChange(AmountSelectionGui.java:148) ~[?:?]
at net.brcdev.shopgui.gui.gui.AmountSelectionGui.createInventory(AmountSelectionGui.java:124) ~[?:?]
at net.brcdev.shopgui.gui.gui.AmountSelectionGui.<init>(AmountSelectionGui.java:39) ~[?:?]
at net.brcdev.shopgui.listener.PlayerListener.clickBuyItem(PlayerListener.java:473) ~[?:?]
at net.brcdev.shopgui.listener.PlayerListener.clickShopGui(PlayerListener.java:224) ~[?:?]
at net.brcdev.shopgui.listener.PlayerListener.onInventoryClick(PlayerListener.java:147) ~[?:?]
at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor1225.execute(Unknown Source) ~[?:?]
at org.bukkit.plugin.EventExecutor.lambda$create$1(EventExecutor.java:69) ~[patched_1.16.5.jar:git-Paper-794]
at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[patched_1.16.5.jar:git-Paper-794]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[patched_1.16.5.jar:git-Paper-794]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:624) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.PlayerConnection.a(PlayerConnection.java:2715) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.PacketPlayInWindowClick.a(SourceFile:32) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.PacketPlayInWindowClick.a(SourceFile:10) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.PlayerConnectionUtils.lambda$ensureMainThread$1(PlayerConnectionUtils.java:35) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.TickTask.run(SourceFile:18) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.MinecraftServer.bb(MinecraftServer.java:1271) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.MinecraftServer.executeNext(MinecraftServer.java:1264) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.MinecraftServer.sleepForTick(MinecraftServer.java:1225) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.MinecraftServer.w(MinecraftServer.java:1139) ~[patched_1.16.5.jar:git-Paper-794]
at net.minecraft.server.v1_16_R3.MinecraftServer.lambda$a$0(MinecraftServer.java:291) ~[patched_1.16.5.jar:git-Paper-794]
at java.lang.Thread.run(Unknown Source) [?:?]
Caused by: java.lang.ClassNotFoundException: net.mmogroup.mmolib.api.item.NBTItem
at org.bukkit.plugin.java.PluginClassLoader.loadClass0(PluginClassLoader.java:155) ~[patched_1.16.5.jar:git-Paper-794]
at org.bukkit.plugin.java.PluginClassLoader.loadClass(PluginClassLoader.java:114) ~[patched_1.16.5.jar:git-Paper-794]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:?]
... 42 more

Lỗi này xảy ra khi mình bấm chọn vào 1 item để mua đồ