Logout

When I try logout (Spring security) I catch error

2018-11-15 17:34:11.757 ERROR 5679 --- [sphere-Shared-6]
 c.v.f.s.c.PushAtmosphereHandler          : Exception in push connection

java.io.IOException: Connection remotely closed for 40a3f381-a2e9-437d-a438-1602bd60d4a0
	at org.atmosphere.websocket.WebSocket.write(WebSocket.java:230) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at org.atmosphere.websocket.WebSocket.write(WebSocket.java:220) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at org.atmosphere.websocket.WebSocket.write(WebSocket.java:46) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at org.atmosphere.cpr.AtmosphereResponseImpl$Stream.write(AtmosphereResponseImpl.java:957) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at org.atmosphere.handler.AbstractReflectorAtmosphereHandler.onStateChange(AbstractReflectorAtmosphereHandler.java:155) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at com.vaadin.flow.server.communication.PushAtmosphereHandler.onStateChange(PushAtmosphereHandler.java:52) ~[flow-server-1.0.5.jar:na]

	at org.atmosphere.cpr.DefaultBroadcaster.invokeOnStateChange(DefaultBroadcaster.java:1037) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at org.atmosphere.cpr.DefaultBroadcaster.prepareInvokeOnStateChange(DefaultBroadcaster.java:1057) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at org.atmosphere.cpr.DefaultBroadcaster.executeAsyncWrite(DefaultBroadcaster.java:871) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at org.atmosphere.cpr.DefaultBroadcaster$2.run(DefaultBroadcaster.java:474) ~[atmosphere-runtime-2.4.24.vaadin1.jar:2.4.24.vaadin1]

	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) ~[na:na]

	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na]

	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na]

	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na]

	at java.base/java.lang.Thread.run(Thread.java:834) ~[na:na]

IconButton iconExitBtn = new IconButton(VaadinIcon.EXIT.create());
Anchor anchorExit = new Anchor();
anchorExit.setHref(LOGOUT_URL);
anchorExit.add(iconExitBtn);

Why is this happening?