[17:10:27] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.8.0_40]
at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[?:1.8.0_40]
at net.minecraft.server.v1_8_R2.SystemUtils.a(SourceFile:61) [creative.jar:git-Spigot-2f787bd-501372f]
at net.minecraft.server.v1_8_R2.MinecraftServer.A(MinecraftServer.java:710) [creative.jar:git-Spigot-2f787bd-501372f]
at net.minecraft.server.v1_8_R2.DedicatedServer.A(DedicatedServer.java:368) [creative.jar:git-Spigot-2f787bd-501372f]
at net.minecraft.server.v1_8_R2.MinecraftServer.z(MinecraftServer.java:651) [creative.jar:git-Spigot-2f787bd-501372f]
at net.minecraft.server.v1_8_R2.MinecraftServer.run(MinecraftServer.java:554) [creative.jar:git-Spigot-2f787bd-501372f]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_40]
Caused by: java.lang.NullPointerException
at net.minecraft.server.v1_8_R2.PlayerConnection.a(PlayerConnection.java:331) ~[creative.jar:git-Spigot-2f787bd-501372f]
at net.minecraft.server.v1_8_R2.PacketPlayInFlying.a(SourceFile:126) ~[creative.jar:git-Spigot-2f787bd-501372f]
at net.minecraft.server.v1_8_R2.PacketPlayInFlying$PacketPlayInPositionLook.a(SourceFile:18) ~[creative.jar:git-Spigot-2f787bd-501372f]
at net.minecraft.server.v1_8_R2.PlayerConnectionUtils$1.run(SourceFile:13) ~[creative.jar:git-Spigot-2f787bd-501372f]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_40]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_40]
at net.minecraft.server.v1_8_R2.SystemUtils.a(SourceFile:60) ~[creative.jar:git-Spigot-2f787bd-501372f]
... 5 more