java.lang.NullPointerException: Cannot invoke "org.bukkit.entity.Player.getUniqueId()" because the return value of "org.bukkit.Bukkit.getPlayer(String)" is null
        at net.TheDgtl.Stargate.listeners.BlockEventListener.selectNetwork(BlockEventListener.java:184) ~[Stargate-0.11.0.5.jar:?]
        at net.TheDgtl.Stargate.listeners.BlockEventListener.onSignChange(BlockEventListener.java:138) ~[Stargate-0.11.0.5.jar:?]
        at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor26.execute(Unknown Source) ~[?:?]
        at org.bukkit.plugin.EventExecutor.lambda$create$1(EventExecutor.java:69) ~[patched_1.17.1.jar:git-Paper-381]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[patched_1.17.1.jar:git-Paper-381]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[patched_1.17.1.jar:git-Paper-381]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:628) ~[patched_1.17.1.jar:git-Paper-381]
        at net.minecraft.server.network.ServerGamePacketListenerImpl.a(ServerGamePacketListenerImpl.java:3060) ~[app:?]
        at net.minecraft.server.network.ServerGamePacketListenerImpl.lambda$handleSignUpdate$20(ServerGamePacketListenerImpl.java:3008) ~[app:?]
        at net.minecraft.server.network.ServerGamePacketListenerImpl.lambda$filterTextPacket$1(ServerGamePacketListenerImpl.java:474) ~[app:?]
        at java.util.concurrent.CompletableFuture$UniAccept.tryFire(CompletableFuture.java:714) ~[?:?]
        at java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:478) ~[?:?]
        at net.minecraft.server.TickTask.run(TickTask.java:18) ~[patched_1.17.1.jar:git-Paper-381]
        at net.minecraft.util.thread.BlockableEventLoop.doRunTask(BlockableEventLoop.java:149) ~[app:?]
        at net.minecraft.util.thread.ReentrantBlockableEventLoop.doRunTask(ReentrantBlockableEventLoop.java:23) ~[app:?]        at net.minecraft.server.MinecraftServer.doRunTask(MinecraftServer.java:1426) ~[patched_1.17.1.jar:git-Paper-381]        at net.minecraft.server.MinecraftServer.shouldRun(MinecraftServer.java:192) ~[patched_1.17.1.jar:git-Paper-381]
        at net.minecraft.util.thread.BlockableEventLoop.pollTask(BlockableEventLoop.java:122) ~[app:?]
        at net.minecraft.server.MinecraftServer.pollTaskInternal(MinecraftServer.java:1404) ~[patched_1.17.1.jar:git-Paper-381]
        at net.minecraft.server.MinecraftServer.pollTask(MinecraftServer.java:1397) ~[patched_1.17.1.jar:git-Paper-381]
        at net.minecraft.util.thread.BlockableEventLoop.managedBlock(BlockableEventLoop.java:132) ~[app:?]
        at net.minecraft.server.MinecraftServer.waitUntilNextTick(MinecraftServer.java:1375) ~[patched_1.17.1.jar:git-Paper-381]
        at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1286) ~[patched_1.17.1.jar:git-Paper-381]        at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:319) ~[patched_1.17.1.jar:git-Paper-381]
        at java.lang.Thread.run(Thread.java:831) ~[?:?]