Namespace exception on start-up - alias already in use

[16] 2019-01-31T12:03:50.031+0000 SEVERE org.forgerock.openidm.config.logging.LogServiceTracker logEntry org.forgerock.openidm.Framework: Bundle: org.forgerock.openidm.servlet [66] [org.forgerock.openidm.ui.context(42)] The activate method has thrown an exception
org.apache.felix.log.LogException: org.osgi.service.http.NamespaceException: alias: '/' is already in use in this or another context
	at org.ops4j.pax.web.service.spi.model.ServerModel.addServletModel(ServerModel.java:130)
	at org.ops4j.pax.web.service.internal.HttpServiceStarted.registerServlet(HttpServiceStarted.java:212)
	at org.ops4j.pax.web.service.internal.HttpServiceStarted.registerServlet(HttpServiceStarted.java:195)
	at org.ops4j.pax.web.service.internal.HttpServiceStarted.registerServlet(HttpServiceStarted.java:179)
	at org.ops4j.pax.web.service.internal.HttpServiceProxy.registerServlet(HttpServiceProxy.java:64)
	at org.forgerock.openidm.ui.internal.service.ResourceServlet.init(ResourceServlet.java:208)
	at org.forgerock.openidm.ui.internal.service.ResourceServlet.activate(ResourceServlet.java:100)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.felix.scr.impl.inject.BaseMethod.invokeMethod(BaseMethod.java:224)
	at org.apache.felix.scr.impl.inject.BaseMethod.access$500(BaseMethod.java:39)
	at org.apache.felix.scr.impl.inject.BaseMethod$Resolved.invoke(BaseMethod.java:617)
	at org.apache.felix.scr.impl.inject.BaseMethod.invoke(BaseMethod.java:501)
	at org.apache.felix.scr.impl.inject.ActivateMethod.invoke(ActivateMethod.java:302)
	at org.apache.felix.scr.impl.inject.ActivateMethod.invoke(ActivateMethod.java:294)
	at org.apache.felix.scr.impl.manager.SingleComponentManager.createImplementationObject(SingleComponentManager.java:297)
	at org.apache.felix.scr.impl.manager.SingleComponentManager.createComponent(SingleComponentManager.java:108)
	at org.apache.felix.scr.impl.manager.SingleComponentManager.getService(SingleComponentManager.java:906)
	at org.apache.felix.scr.impl.manager.SingleComponentManager.getServiceInternal(SingleComponentManager.java:879)
	at org.apache.felix.scr.impl.manager.AbstractComponentManager.activateInternal(AbstractComponentManager.java:748)
	at org.apache.felix.scr.impl.manager.DependencyManager$SingleStaticCustomizer.addedService(DependencyManager.java:1012)
	at org.apache.felix.scr.impl.manager.DependencyManager$SingleStaticCustomizer.addedService(DependencyManager.java:968)
	at org.apache.felix.scr.impl.manager.ServiceTracker$Tracked.customizerAdded(ServiceTracker.java:1215)
	at org.apache.felix.scr.impl.manager.ServiceTracker$Tracked.customizerAdded(ServiceTracker.java:1136)
	at org.apache.felix.scr.impl.manager.ServiceTracker$AbstractTracked.trackAdding(ServiceTracker.java:945)
	at org.apache.felix.scr.impl.manager.ServiceTracker$AbstractTracked.track(ServiceTracker.java:881)
	at org.apache.felix.scr.impl.manager.ServiceTracker$Tracked.serviceChanged(ServiceTracker.java:1167)
	at org.apache.felix.scr.impl.BundleComponentActivator$ListenerInfo.serviceChanged(BundleComponentActivator.java:127)
	at org.apache.felix.framework.EventDispatcher.invokeServiceListenerCallback(EventDispatcher.java:990)
	at org.apache.felix.framework.EventDispatcher.fireEventImmediately(EventDispatcher.java:838)
	at org.apache.felix.framework.EventDispatcher.fireServiceEvent(EventDispatcher.java:545)
	at org.apache.felix.framework.Felix.fireServiceEvent(Felix.java:4595)
	at org.apache.felix.framework.Felix.registerService(Felix.java:3587)
	at org.apache.felix.framework.BundleContextImpl.registerService(BundleContextImpl.java:348)
	at org.ops4j.pax.web.service.internal.Activator.updateController(Activator.java:357)
	at org.ops4j.pax.web.service.internal.Activator$3.run(Activator.java:294)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)