java.lang.UnsupportedOperationException: Not supported yet.

[12:56:55] [Server-Worker-2/ERROR]: Couldn't load function at reload:functions/datapackreload.mcfunction
java.util.concurrent.CompletionException: java.lang.UnsupportedOperationException: Not supported yet.
	at java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:273) ~[?:1.8.0_212]
	at java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:280) [?:1.8.0_212]
	at java.util.concurrent.CompletableFuture.uniApply(CompletableFuture.java:604) [?:1.8.0_212]
	at java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:577) [?:1.8.0_212]
	at java.util.concurrent.CompletableFuture$Completion.exec(CompletableFuture.java:443) [?:1.8.0_212]
	at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289) [?:1.8.0_212]
	at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056) [?:1.8.0_212]
	at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692) [?:1.8.0_212]
	at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157) [?:1.8.0_212]
Caused by: java.lang.UnsupportedOperationException: Not supported yet.
	at net.minecraft.server.v1_14_R1.ICommandListener$1.getBukkitSender(ICommandListener.java:27) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at net.minecraft.server.v1_14_R1.CommandListenerWrapper.getBukkitSender(CommandListenerWrapper.java:255) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at net.minecraft.server.v1_14_R1.CommandListenerWrapper.hasPermission(CommandListenerWrapper.java:137) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at net.minecraft.server.v1_14_R1.CommandListenerWrapper.hasPermission(CommandListenerWrapper.java:127) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at net.minecraft.server.v1_14_R1.CommandScoreboard.c(SourceFile:64) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at com.mojang.brigadier.tree.CommandNode.canUse(CommandNode.java:78) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at com.mojang.brigadier.CommandDispatcher.parseNodes(CommandDispatcher.java:357) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at com.mojang.brigadier.CommandDispatcher.parse(CommandDispatcher.java:347) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at net.minecraft.server.v1_14_R1.CustomFunction.a(CustomFunction.java:51) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at net.minecraft.server.v1_14_R1.CustomFunctionData.lambda$7(CustomFunctionData.java:168) ~[spigot-1.14.4.jar:git-Spigot-e5b1b5d-1ec1b05]
	at java.util.concurrent.CompletableFuture.uniApply(CompletableFuture.java:602) ~[?:1.8.0_212]
	... 6 more