An exception occurs when I try to enable some of plugins, for example:

Error occurred while enabling QualityArmory v1.1.135 (Is it up to date?)
java.lang.NullPointerException: null
at me.zombie_striker.qg.QAMain.onEnable(QAMain.java:383) ~[?:?]
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:265) ~[Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:339) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:409) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at com.rylinaux.plugman.util.PluginUtil.load(PluginUtil.java:366) [PlugMan.jar:?]
at com.rylinaux.plugman.command.LoadCommand.execute(LoadCommand.java:114) [PlugMan.jar:?]
at com.rylinaux.plugman.PlugManCommandHandler.onCommand(PlugManCommandHandler.java:95) [PlugMan.jar:?]
at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:140) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at org.bukkit.craftbukkit.v1_13_R2.CraftServer.dispatchCommand(CraftServer.java:684) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at org.bukkit.craftbukkit.v1_13_R2.CraftServer.dispatchServerCommand(CraftServer.java:670) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at net.minecraft.server.v1_13_R2.DedicatedServer.handleCommandQueue(DedicatedServer.java:423) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at net.minecraft.server.v1_13_R2.DedicatedServer.b(DedicatedServer.java:383) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at net.minecraft.server.v1_13_R2.MinecraftServer.a(MinecraftServer.java:792) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at net.minecraft.server.v1_13_R2.MinecraftServer.run(MinecraftServer.java:695) [Craftbukkit-1.13.2.jar:git-Bukkit-f40143e]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_45]