advancedspawnerserror

[12:13:40 INFO]: [AdvancedSpawners] Loaded 28 spawners.
[12:13:40 INFO]: [AdvancedSpawners] Using language file 'en_US.yml'.
[12:13:40 ERROR]: [AdvancedSpawners] Failed to check and correct invalid configurated levels.
java.lang.NullPointerException: null
        at me.greenadine.advancedspawners.AdvancedSpawners.checkLevels(AdvancedSpawners.java:203) ~[?:?]
        at me.greenadine.advancedspawners.AdvancedSpawners.onEnable(AdvancedSpawners.java:108) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:263) ~[patched_1.14.4.jar:git-Paper-243]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:338) ~[patched_1.14.4.jar:git-Paper-243]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:420) ~[patched_1.14.4.jar:git-Paper-243]
        at org.bukkit.craftbukkit.v1_14_R1.CraftServer.enablePlugin(CraftServer.java:467) ~[patched_1.14.4.jar:git-Paper-243]
        at org.bukkit.craftbukkit.v1_14_R1.CraftServer.enablePlugins(CraftServer.java:381) ~[patched_1.14.4.jar:git-Paper-243]
        at net.minecraft.server.v1_14_R1.MinecraftServer.a(MinecraftServer.java:474) ~[patched_1.14.4.jar:git-Paper-243]
        at net.minecraft.server.v1_14_R1.DedicatedServer.init(DedicatedServer.java:290) ~[patched_1.14.4.jar:git-Paper-243]
        at net.minecraft.server.v1_14_R1.MinecraftServer.run(MinecraftServer.java:876) ~[patched_1.14.4.jar:git-Paper-243]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_241]
[12:13:40 INFO]: [AdvancedSpawners] If this problem persists, please report to plugin developer.