RS: delete a method in the booking configuration of learn resource

User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:52.0) Gecko/20100101 Firefox/52.0 SeaMonkey/2.49.2
Log msg: **RedScreen** Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect) : [org.olat.resource.accesscontrol.model.OfferImpl#66486334] 

ffo_main_access_configuration
org.olat.core.gui.components.form.flexible.impl.FormWrapperContainer
org.olat.core.gui.components.form.flexible.impl.FormEvent
	done
	com:done,org.olat.core.gui.components.form.flexible.impl.FormEvent@2f23a1
org.olat.resource.accesscontrol.ui.AccessConfigurationController      
org.olat.repository.ui.author.AuthoringEditAccessController
org.olat.course.run.CourseRuntimeController
org.olat.core.commons.fullWebApp.BaseFullWebappController

Cause:
stack of 1.cause::org.olat.core.logging.OLATRuntimeException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect) : [org.olat.resource.accesscontrol.model.OfferImpl#66486334] ->
at org.olat.core.gui.exception.ExceptionWindowController.(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:589)
at org.olat.core.gui.components.Window.doDispatchRequest(Window.java:282)
at org.olat.core.gui.components.AbstractComponent.dispatchRequest(AbstractComponent.java:193)
at org.olat.dispatcher.AuthenticatedDispatcher.processValidDispatchURI(AuthenticatedDispatcher.java:273)
at org.olat.dispatcher.AuthenticatedDispatcher.execute(AuthenticatedDispatcher.java:190)
at org.olat.core.servlets.OpenOLATServlet.executeUserRequest(OpenOLATServlet.java:294)
at org.olat.core.servlets.OpenOLATServlet.doPost(OpenOLATServlet.java:237)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:661)

stack of 2.cause::javax.persistence.OptimisticLockException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect) : [org.olat.resource.accesscontrol.model.OfferImpl#66486334] ->
at org.hibernate.internal.ExceptionConverterImpl.wrapStaleStateException(ExceptionConverterImpl.java:199)
at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:88)
at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:157)
at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:164)
at org.hibernate.internal.SessionImpl.fireMerge(SessionImpl.java:895)
at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:869)
at org.olat.resource.accesscontrol.manager.ACOfferDAO.saveOffer(ACOfferDAO.java:166)
at org.olat.resource.accesscontrol.manager.ACOfferDAO.deleteOffer(ACOfferDAO.java:156)
at org.olat.resource.accesscontrol.manager.ACFrontendManager.deleteOffer(ACFrontendManager.java:258)
at org.olat.resource.accesscontrol.ui.AccessConfigurationController.removeMethod(AccessConfigurationController.java:369)
at org.olat.resource.accesscontrol.ui.AccessConfigurationController.formInnerEvent(AccessConfigurationController.java:255)

stack of 3.cause::org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect) : [org.olat.resource.accesscontrol.model.OfferImpl#66486334] ->
at org.hibernate.event.internal.DefaultMergeEventListener.entityIsDetached(DefaultMergeEventListener.java:322)
at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:170)
at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:69)
at org.hibernate.internal.SessionImpl.fireMerge(SessionImpl.java:883)
at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:869)
at org.olat.resource.accesscontrol.manager.ACOfferDAO.saveOffer(ACOfferDAO.java:166)
at org.olat.resource.accesscontrol.manager.ACOfferDAO.deleteOffer(ACOfferDAO.java:156)
at org.olat.resource.accesscontrol.manager.ACFrontendManager.deleteOffer(ACFrontendManager.java:258)
at org.olat.resource.accesscontrol.ui.AccessConfigurationController.removeMethod(AccessConfigurationController.java:369)
at org.olat.resource.accesscontrol.ui.AccessConfigurationController.formInnerEvent(AccessConfigurationController.java:255)
at org.olat.core.gui.components.form.flexible.impl.FormBasicController.event(FormBasicController.java:421)2019-05-02 13:58:19,100