RS add a booking method to a group

User-Agent: Mozilla/5.0 (Windows NT 6.1; Trident/7.0; rv:11.0) like Gecko
Log msg: **RedScreen** could not initialize proxy - no Session
<dispatchinfo>
	<componentinfo>
		<compname>ffo_main_null</compname>
		<compclass>org.olat.core.gui.components.form.flexible.impl.FormWrapperContainer</compclass>
		<extendedinfo>n/a</extendedinfo>
		<event>
			<class&gt;org.olat.core.gui.control.Event</class&gt;
			<command>validation ok</command>
			<tostring>com:validation ok,org.olat.core.gui.control.Event@d62b3f02</tostring>
		</event>
	</componentinfo>
	<controllerinfo> 
		<controllername>org.olat.resource.accesscontrol.provider.free.ui.FreeAccessConfigurationController</controllername>
		<controllername>org.olat.resource.accesscontrol.ui.AccessConfigurationController</controllername>
		<controllername>org.olat.group.ui.edit.BusinessGroupEditController</controllername> 
		<controllername>org.olat.group.ui.run.BusinessGroupMainRunController</controllername> 
		<controllername>org.olat.core.commons.fullWebApp.BaseFullWebappController</controllername>
	</controllerinfo>
</dispatchinfo>

Cause:  stack of 1.cause::org.olat.core.logging.OLATRuntimeException: could not initialize proxy - no Session
-> at org.olat.core.gui.exception.ExceptionWindowController.<init>(ExceptionWindowController.java:116)
   at org.olat.core.gui.exception.MsgFactory.createMessageChiefController(MsgFactory.java:57)
   at org.olat.core.gui.exception.MsgFactory.createMessageChiefController(MsgFactory.java:46)
   at org.olat.core.gui.components.Window.dispatchRequest(Window.java:524)
   at org.olat.core.gui.components.Window.doDispatchRequest(Window.java:228)
   at org.olat.core.gui.components.AbstractComponent.dispatchRequest(AbstractComponent.java:192)
   at org.olat.dispatcher.AuthenticatedDispatcher.processValidDispatchURI(AuthenticatedDispatcher.java:241)
   at org.olat.dispatcher.AuthenticatedDispatcher.execute(AuthenticatedDispatcher.java:197)
   at org.olat.core.servlets.OpenOLATServlet.executeUserRequest(OpenOLATServlet.java:269)
   at org.olat.core.servlets.OpenOLATServlet.doPost(OpenOLATServlet.java:212)
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
stack of 2.cause::org.hibernate.LazyInitializationException: could not initialize proxy - no Session
-> at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:165)
   at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:286)
   at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:185)
   at org.olat.basesecurity.model.GroupImpl_$$_jvstcb7_1c.getKey(GroupImpl_$$_jvstcb7_1c.java)
   at org.olat.repository.manager.RepositoryEntryRelationDAO.countRelations(RepositoryEntryRelationDAO.java:367)
   at org.olat.group.manager.BusinessGroupRelationDAO.countResources(BusinessGroupRelationDAO.java:269)
   at org.olat.group.manager.BusinessGroupServiceImpl.hasResources(BusinessGroupServiceImpl.java:1384)
   at org.olat.group.ui.edit.BusinessGroupEditController.setAllTabs(BusinessGroupEditController.java:179)
   at org.olat.group.ui.edit.BusinessGroupEditController.event(BusinessGroupEditController.java:298)
   at org.olat.core.gui.control.DefaultController$1.run(DefaultController.java:241)
   at org.olat.core.logging.activity.ThreadLocalUserActivityLoggerInstaller.runWithUserActivityLogger(ThreadLocalUserActivityLoggerInstaller.java:108)