[09:10:40 ERROR]: Error occurred while enabling tpLogin v1.5 (Is it up to date?)

java.lang.IllegalArgumentException: Plugin already initialized!
        at org.bukkit.plugin.java.PluginClassLoader.initialize(PluginClassLoader
.java:98) ~[spigot.jar:git-Spigot-1294]
        at org.bukkit.plugin.java.JavaPlugin.<init>(JavaPlugin.java:59) ~[spigot
.jar:git-Spigot-1294]
        at com.volcanicplaza.tpLogin.PlayerListener.<init>(PlayerListener.java:1
5) ~[?:?]
        at com.volcanicplaza.tpLogin.tpLogin.onEnable(tpLogin.java:72) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:250) ~[s
pigot.jar:git-Spigot-1294]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader
.java:350) [spigot.jar:git-Spigot-1294]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManage
r.java:385) [spigot.jar:git-Spigot-1294]
        at org.bukkit.craftbukkit.v1_7_R1.CraftServer.loadPlugin(CraftServer.jav
a:303) [spigot.jar:git-Spigot-1294]
        at org.bukkit.craftbukkit.v1_7_R1.CraftServer.enablePlugins(CraftServer.
java:285) [spigot.jar:git-Spigot-1294]
        at net.minecraft.server.v1_7_R1.MinecraftServer.m(MinecraftServer.java:3
47) [spigot.jar:git-Spigot-1294]
        at net.minecraft.server.v1_7_R1.MinecraftServer.g(MinecraftServer.java:3
24) [spigot.jar:git-Spigot-1294]
        at net.minecraft.server.v1_7_R1.MinecraftServer.a(MinecraftServer.java:2
80) [spigot.jar:git-Spigot-1294]
        at net.minecraft.server.v1_7_R1.DedicatedServer.init(DedicatedServer.jav
a:186) [spigot.jar:git-Spigot-1294]
        at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java
:436) [spigot.jar:git-Spigot-1294]
        at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:6
17) [spigot.jar:git-Spigot-1294]
Caused by: java.lang.IllegalStateException: Initial initialization
        at org.bukkit.plugin.java.PluginClassLoader.initialize(PluginClassLoader
.java:101) ~[spigot.jar:git-Spigot-1294]
        at org.bukkit.plugin.java.JavaPlugin.<init>(JavaPlugin.java:59) ~[spigot
.jar:git-Spigot-1294]
        at com.volcanicplaza.tpLogin.tpLogin.<init>(tpLogin.java:16) ~[?:?]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
 ~[?:1.7.0_45]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
 ~[?:1.7.0_45]
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Sou
rce) ~[?:1.7.0_45]
        at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:1.7.0_4
5]
        at java.lang.Class.newInstance(Unknown Source) ~[?:1.7.0_45]
        at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.jav
a:52) ~[spigot.jar:git-Spigot-1294]
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.j
ava:133) ~[spigot.jar:git-Spigot-1294]
        at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.
java:309) ~[spigot.jar:git-Spigot-1294]
        at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager
.java:231) ~[spigot.jar:git-Spigot-1294]
        at org.bukkit.craftbukkit.v1_7_R1.CraftServer.loadPlugins(CraftServer.ja
va:260) ~[spigot.jar:git-Spigot-1294]
        at net.minecraft.server.v1_7_R1.DedicatedServer.init(DedicatedServer.jav
a:135) ~[spigot.jar:git-Spigot-1294]
        ... 2 more