CustomDeathDrops v1.1

[17:15:09] [Server thread/INFO]: [CustomDeathDrops] Enabling CustomDeathDrops v1.1
[17:15:09] [Server thread/ERROR]: Error occurred while enabling CustomDeathDrops v1.1 (Is it up to date?)
java.lang.NoSuchMethodError: org.bukkit.configuration.file.YamlConfiguration.loadConfiguration(Ljava/io/InputStream;)Lorg/bukkit/configuration/file/YamlConfiguration;
    at me.xMrPoi.CustomDeathDrops.MyConfig.<init>(MyConfig.java:27) ~[?:?]
    at me.xMrPoi.CustomDeathDrops.MyConfigManager.getNewConfig(MyConfigManager.java:34) ~[?:?]
    at me.xMrPoi.CustomDeathDrops.Main.onEnable(Main.java:22) ~[?:?]
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264) ~[spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:337) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:403) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:381) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:330) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at net.minecraft.server.v1_12_R1.MinecraftServer.t(MinecraftServer.java:422) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at net.minecraft.server.v1_12_R1.MinecraftServer.l(MinecraftServer.java:383) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:338) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:272) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:545) [spigot-1.12.2.jar:git-Spigot-2086bb0-d0a3620]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_171]