After joining the queue, it is blocked in the requestqueue, and subsequent requests cannot be allocated

 18926 java.lang.NullPointerException: null
  18927     at org.jivesoftware.xmpp.workgroup.RequestQueue.getStatusPresence(RequestQueue.java:352) ~[fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18928     at org.jivesoftware.xmpp.workgroup.RequestQueue.sendStatus(RequestQueue.java:320) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18929     at org.jivesoftware.xmpp.workgroup.AgentSessionList.broadcastQueueStatus(AgentSessionList.java:62) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18930     at org.jivesoftware.xmpp.workgroup.RequestQueue.addRequest(RequestQueue.java:305) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18931     at org.jivesoftware.xmpp.workgroup.routing.RoutingManager.routeRequest(RoutingManager.java:139) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18932     at org.jivesoftware.xmpp.workgroup.Workgroup.queueRequest(Workgroup.java:429) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18933     at org.jivesoftware.xmpp.workgroup.WorkgroupIQHandler.handleIQSet(WorkgroupIQHandler.java:137) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18934     at org.jivesoftware.xmpp.workgroup.WorkgroupIQHandler.process(WorkgroupIQHandler.java:87) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18935     at org.jivesoftware.xmpp.workgroup.Workgroup.process(Workgroup.java:457) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18936     at org.jivesoftware.xmpp.workgroup.Workgroup.process(Workgroup.java:480) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18937     at org.jivesoftware.xmpp.workgroup.WorkgroupManager.processPacket(WorkgroupManager.java:684) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18938     at org.jivesoftware.openfire.component.InternalComponentManager$RoutableComponents.process(InternalComponentManager.java:859) [xmppserver-4.6.4.jar:4.6.4]
  18939     at org.jivesoftware.openfire.spi.RoutingTableImpl.routeToComponent(RoutingTableImpl.java:451) [xmppserver-4.6.4.jar:4.6.4]
  18940     at org.jivesoftware.openfire.spi.RoutingTableImpl.routePacket(RoutingTableImpl.java:266) [xmppserver-4.6.4.jar:4.6.4]
  18941     at org.jivesoftware.openfire.IQRouter.handle(IQRouter.java:340) [xmppserver-4.6.4.jar:4.6.4]
  18942     at org.jivesoftware.openfire.IQRouter.route(IQRouter.java:105) [xmppserver-4.6.4.jar:4.6.4]
  18943     at org.jivesoftware.openfire.spi.PacketRouterImpl.route(PacketRouterImpl.java:74) [xmppserver-4.6.4.jar:4.6.4]
  18944     at org.jivesoftware.openfire.SessionPacketRouter.route(SessionPacketRouter.java:104) [xmppserver-4.6.4.jar:4.6.4]
  18945     at org.jivesoftware.openfire.SessionPacketRouter.route(SessionPacketRouter.java:63) [xmppserver-4.6.4.jar:4.6.4]
  18946     at org.jivesoftware.openfire.http.HttpSession.sendPendingPackets(HttpSession.java:612) [xmppserver-4.6.4.jar:4.6.4]
  18947     at org.jivesoftware.openfire.http.HttpSession$HttpPacketSender.run(HttpSession.java:1329) [xmppserver-4.6.4.jar:4.6.4]
  18948     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_144]
  18949     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_144]
  18950     at java.lang.Thread.run(Thread.java:748) [?:1.8.0_144]
18953     at org.jivesoftware.xmpp.workgroup.RequestQueue.getDetailedStatusPresence(RequestQueue.java:417) ~[fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18954     at org.jivesoftware.xmpp.workgroup.RequestQueue.sendDetailedStatus(RequestQueue.java:332) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18955     at org.jivesoftware.xmpp.workgroup.AgentSessionList.broadcastQueueStatus(AgentSessionList.java:63) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18956     at org.jivesoftware.xmpp.workgroup.RequestQueue.addRequest(RequestQueue.java:305) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18957     at org.jivesoftware.xmpp.workgroup.routing.RoutingManager.routeRequest(RoutingManager.java:139) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18958     at org.jivesoftware.xmpp.workgroup.Workgroup.queueRequest(Workgroup.java:429) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18959     at org.jivesoftware.xmpp.workgroup.WorkgroupIQHandler.handleIQSet(WorkgroupIQHandler.java:137) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18960     at org.jivesoftware.xmpp.workgroup.WorkgroupIQHandler.process(WorkgroupIQHandler.java:87) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18961     at org.jivesoftware.xmpp.workgroup.Workgroup.process(Workgroup.java:457) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18962     at org.jivesoftware.xmpp.workgroup.Workgroup.process(Workgroup.java:480) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18963     at org.jivesoftware.xmpp.workgroup.WorkgroupManager.processPacket(WorkgroupManager.java:684) [fastpath-4.5.0-SNAPSHOT.jar!/:?]
  18964     at org.jivesoftware.openfire.component.InternalComponentManager$RoutableComponents.process(InternalComponentManager.java:859) [xmppserver-4.6.4.jar:4.6.4]
  18965     at org.jivesoftware.openfire.spi.RoutingTableImpl.routeToComponent(RoutingTableImpl.java:451) [xmppserver-4.6.4.jar:4.6.4]
  18966     at org.jivesoftware.openfire.spi.RoutingTableImpl.routePacket(RoutingTableImpl.java:266) [xmppserver-4.6.4.jar:4.6.4]
  18967     at org.jivesoftware.openfire.IQRouter.handle(IQRouter.java:340) [xmppserver-4.6.4.jar:4.6.4]
  18968     at org.jivesoftware.openfire.IQRouter.route(IQRouter.java:105) [xmppserver-4.6.4.jar:4.6.4]
  18969     at org.jivesoftware.openfire.spi.PacketRouterImpl.route(PacketRouterImpl.java:74) [xmppserver-4.6.4.jar:4.6.4]
  18970     at org.jivesoftware.openfire.SessionPacketRouter.route(SessionPacketRouter.java:104) [xmppserver-4.6.4.jar:4.6.4]
  18971     at org.jivesoftware.openfire.SessionPacketRouter.route(SessionPacketRouter.java:63) [xmppserver-4.6.4.jar:4.6.4]
  18972     at org.jivesoftware.openfire.http.HttpSession.sendPendingPackets(HttpSession.java:612) [xmppserver-4.6.4.jar:4.6.4]
  18973     at org.jivesoftware.openfire.http.HttpSession$HttpPacketSender.run(HttpSession.java:1329) [xmppserver-4.6.4.jar:4.6.4]
  18974     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_144]
  18975     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_144]
  18976     at java.lang.Thread.run(Thread.java:748) [?:1.8.0_144]

It may be caused by the userrequest object being empty