[11:10:34] [Server thread/INFO]: Eik0_ issued server command: /presentman spawn yeet
[11:10:34] [Server thread/ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'presentman' in plugin RewardPRO v4.1.3
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:48) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at org.bukkit.craftbukkit.v1_13_R2.CraftServer.dispatchCommand(CraftServer.java:704) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.PlayerConnection.handleCommand(PlayerConnection.java:1621) ~[?:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.PlayerConnection.a(PlayerConnection.java:1461) ~[?:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.PacketPlayInChat.a(PacketPlayInChat.java:45) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.PacketPlayInChat.a(PacketPlayInChat.java:1) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.PlayerConnectionUtils.lambda$0(PlayerConnectionUtils.java:9) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_212]
	at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_212]
	at net.minecraft.server.v1_13_R2.SystemUtils.a(SourceFile:199) [Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.MinecraftServer.b(MinecraftServer.java:896) [Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.DedicatedServer.b(DedicatedServer.java:417) [Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.MinecraftServer.a(MinecraftServer.java:831) [Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at net.minecraft.server.v1_13_R2.MinecraftServer.run(MinecraftServer.java:729) [Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_212]
Caused by: java.lang.IllegalArgumentException: Material cannot be null
	at org.apache.commons.lang.Validate.notNull(Validate.java:192) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at org.bukkit.inventory.ItemStack.<init>(ItemStack.java:71) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at org.bukkit.inventory.ItemStack.<init>(ItemStack.java:59) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at org.bukkit.inventory.ItemStack.<init>(ItemStack.java:47) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at org.bukkit.inventory.ItemStack.<init>(ItemStack.java:37) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	at eu.superm.minecraft.rewardpro.f.d.a(PresentmanSpawnInventory.java:63) ~[?:?]
	at eu.superm.minecraft.rewardpro.f.d.<init>(PresentmanSpawnInventory.java:41) ~[?:?]
	at eu.superm.minecraft.rewardpro.mainclasses.PlayerCommandHandler.onCommand(PlayerCommandHandler.java:237) ~[?:?]
	at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[Spigot.jar:git-Spigot-1a3504a-84f3da3]
	... 15 more