/cod join error

[01:13:51] [Server thread/INFO]: RedstoneRail819 issued server command: /cod join
[01:13:51] [Server thread/ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'cod' in plugin COM-Warfare v2.12.8
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:47) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:149) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at org.bukkit.craftbukkit.v1_14_R1.CraftServer.dispatchCommand(CraftServer.java:710) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.PlayerConnection.handleCommand(PlayerConnection.java:1641) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.PlayerConnection.a(PlayerConnection.java:1481) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.PacketPlayInChat.a(PacketPlayInChat.java:47) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.PacketPlayInChat.a(PacketPlayInChat.java:1) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.PlayerConnectionUtils.lambda$0(PlayerConnectionUtils.java:19) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.TickTask.run(SourceFile:18) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.executeTask(SourceFile:144) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.executeNext(SourceFile:118) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.MinecraftServer.aX(MinecraftServer.java:910) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.MinecraftServer.executeNext(MinecraftServer.java:903) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.awaitTasks(SourceFile:127) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.MinecraftServer.sleepForTick(MinecraftServer.java:887) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at net.minecraft.server.v1_14_R1.MinecraftServer.run(MinecraftServer.java:820) [spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_221]
Caused by: java.lang.NullPointerException: Name is null
        at java.lang.Enum.valueOf(Unknown Source) ~[?:1.8.0_221]
        at org.bukkit.Material.valueOf(Material.java:1) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        at com.rhetorical.cod.loadouts.LoadoutManager.getDefaultSecondary(LoadoutManager.java:252) ~[?:?]
        at com.rhetorical.cod.inventories.ShopManager.loadPurchaseData(ShopManager.java:280) ~[?:?]
        at com.rhetorical.cod.inventories.ShopManager.checkForNewGuns(ShopManager.java:459) ~[?:?]
        at com.rhetorical.cod.game.GameManager.loadPlayerData(GameManager.java:220) ~[?:?]
        at com.rhetorical.cod.game.GameManager.findMatch(GameManager.java:135) ~[?:?]
        at com.rhetorical.cod.Main.onCommand(Main.java:432) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:45) ~[spigot-1.14.4.jar:git-Spigot-9de398a-9c887d4]
        ... 17 more