Help with error that I could not read.

I'm trying to create a set tag plugin for players. But for some reason I start and using the command gives this error.

Code:

[21:10:35 ERROR]: null
org.bukkit.command.CommandException: Unhandled exception executing command 'tag' in plugin sTags v1.0
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:46) ~[spigot.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) ~[spigot.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchCommand(CraftServer.java:641) ~[spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PlayerConnection.handleCommand(PlayerConnection.java:1162) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PlayerConnection.a(PlayerConnection.java:997) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:45) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PacketPlayInChat.a(PacketPlayInChat.java:1) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.PlayerConnectionUtils$1.run(SourceFile:13) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_281]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_281]
        at net.minecraft.server.v1_8_R3.SystemUtils.a(SourceFile:44) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:715) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:374) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:654) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:557) [spigot.jar:git-Spigot-db6de12-18fbb24]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_281]
Caused by: java.lang.NoClassDefFoundError: com/nametagedit/plugin/NametagEdit
        at me.servidor.tags.Tags.onCommand(Tags.java:107) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[spigot.jar:git-Spigot-db6de12-18fbb24]
        ... 15 more
Caused by: java.lang.ClassNotFoundException: com.nametagedit.plugin.NametagEdit
        at java.net.URLClassLoader.findClass(Unknown Source) ~[?:1.8.0_281]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:101) ~[spigot.jar:git-Spigot-db6de12-18fbb24]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot.jar:git-Spigot-db6de12-18fbb24]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_281]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_281]
        at me.servidor.tags.Tags.onCommand(Tags.java:107) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[spigot.jar:git-Spigot-db6de12-18fbb24]
        ... 15 more

 

Yes, I ended up realizing it yesterday but I didn't know if I could delete the post. Thanks.