Console Error on Join for Voice.

[09:35:50] [ ERROR] [JDA] One of the EventListeners had an uncaught exception
java.lang.IllegalStateException: This message event did not happen in a private channel
        at net.dv8tion.jda.api.events.message.GenericMessageEvent.getPrivateChannel(GenericMessageEvent.java:169)
        at gensokyobot.event.EventListenerBoat.onMessageReceived(EventListenerBoat.java:56)
        at net.dv8tion.jda.api.hooks.ListenerAdapter.onEvent(ListenerAdapter.java:375)
        at net.dv8tion.jda.api.hooks.InterfacedEventManager.handle(InterfacedEventManager.java:96)
        at net.dv8tion.jda.internal.hooks.EventManagerProxy.handle(EventManagerProxy.java:64)
        at net.dv8tion.jda.internal.JDAImpl.handleEvent(JDAImpl.java:148)
        at net.dv8tion.jda.internal.handle.MessageCreateHandler.handleInternally(MessageCreateHandler.java:122)
        at net.dv8tion.jda.internal.handle.SocketHandler.handle(SocketHandler.java:37)
        at net.dv8tion.jda.internal.requests.WebSocketClient.onDispatch(WebSocketClient.java:838)
        at net.dv8tion.jda.internal.requests.WebSocketClient.onEvent(WebSocketClient.java:737)
        at net.dv8tion.jda.internal.requests.WebSocketClient.handleEvent(WebSocketClient.java:716)
        at net.dv8tion.jda.internal.requests.WebSocketClient.onBinaryMessage(WebSocketClient.java:876)
        at com.neovisionaries.ws.client.ListenerManager.callOnBinaryMessage(ListenerManager.java:368)
        at com.neovisionaries.ws.client.ReadingThread.callOnBinaryMessage(ReadingThread.java:270)
        at com.neovisionaries.ws.client.ReadingThread.handleBinaryFrame(ReadingThread.java:990)
        at com.neovisionaries.ws.client.ReadingThread.handleFrame(ReadingThread.java:749)
        at com.neovisionaries.ws.client.ReadingThread.main(ReadingThread.java:108)
        at com.neovisionaries.ws.client.ReadingThread.runMain(ReadingThread.java:64)
        at com.neovisionaries.ws.client.WebSocketThread.run(WebSocketThread.java:45)