scoreboard/sidebar update error ?

so i'm using a method i saw on youtube in order to update my scoreboard each time a player gets a kill or dies the code seems to work but i'm getting a console error that i'm getting each time i die and i'm pretty sure i'll be getting each time i kill a player is:

Code:

[23:56:58 ERROR]: Could not pass event PlayerDeathEvent to SideBar v1.5 java.lang.NullPointerException: null at me.k.sidebar.SideBar.updateScoreboard(SideBar.java:210) ~[?:?] at me.k.sidebar.SBListener.KillPlayer(SBListener.java:47) ~[?:?] at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor266.execute(Unknown Source) ~[?:?] at org.bukkit.plugin.EventExecutor.lambda$create(EventExecutor.java:69) ~[patched_1.14.4.jar:git-Paper-243] at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[patched_1.14.4.jar:git-Paper-243] at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[patched_1.14.4.jar:git-Paper-243] at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:545) ~[patched_1.14.4.jar:git-Paper-243] at org.bukkit.craftbukkit.v1_14_R1.event.CraftEventFactory.callPlayerDeathEvent(CraftEventFactory.java:775) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.EntityPlayer.die(EntityPlayer.java:586) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.EntityLiving.damageEntity(EntityLiving.java:1198) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.EntityHuman.damageEntity(EntityHuman.java:786) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.EntityPlayer.damageEntity(EntityPlayer.java:757) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.EntityLiving.killEntity(EntityLiving.java:177) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.CommandKill.a(SourceFile:30) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.CommandKill.a(SourceFile:23) ~[patched_1.14.4.jar:git-Paper-243] at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:262) ~[patched_1.14.4.jar:git-Paper-243] at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:176) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.CommandDispatcher.a(CommandDispatcher.java:172) ~[patched_1.14.4.jar:git-Paper-243] at org.bukkit.craftbukkit.v1_14_R1.command.VanillaCommandWrapper.execute(VanillaCommandWrapper.java:45) ~[patched_1.14.4.jar:git-Paper-243] at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:159) ~[patched_1.14.4.jar:git-Paper-243] at org.bukkit.craftbukkit.v1_14_R1.CraftServer.dispatchCommand(CraftServer.java:739) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.PlayerConnection.handleCommand(PlayerConnection.java:1804) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.PlayerConnection.a(PlayerConnection.java:1612) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.PacketPlayInChat.a(PacketPlayInChat.java:47) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.PacketPlayInChat.a(PacketPlayInChat.java:5) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.PlayerConnectionUtils.lambda$ensureMainThread$0(PlayerConnectionUtils.java:23) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.TickTask.run(SourceFile:18) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.MinecraftServer.aX(MinecraftServer.java:1029) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.MinecraftServer.executeNext(MinecraftServer.java:1022) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.MinecraftServer.sleepForTick(MinecraftServer.java:1006) ~[patched_1.14.4.jar:git-Paper-243] at net.minecraft.server.v1_14_R1.MinecraftServer.run(MinecraftServer.java:929) ~[patched_1.14.4.jar:git-Paper-243] at java.lang.Thread.run(Unknown Source) [?:1.8.0_144]

thing is i'm not using a PlayerDeathEvent but rather an EntityDeathEvent in the class SBListener and in the class SBListener line 47 is

Code:

SideBar.updateScoreboard(player2);

and in the main class SideBar line 210 is

Code:

Score s14 = o.getScore(ChatColor.GOLD + "" + ChatColor.BOLD + "Kills");

Though i think the error comes from this line

Code:

Objective o = player.getScoreboard().getObjective("Kills") != null ? player.getScoreboard().getObjective("kills") : player.getScoreboard().registerNewObjective("kills", "dummy", "");

And i'm not really sure how to fix it so i'd be really thankful if someone can help me