There has been an Error!

Reason:
        org.apache.turbine.util.TurbineException: Error rendering Velocity template: screens/EcEduCourseDetail.vm: Invocation of method 'clean' in  class com.insite.infoservis.utils.html.AdvancedHtmlCleaner threw exception class java.lang.NullPointerException : Cannot invoke "jodd.lagarto.dom.Node.insertChild(jodd.lagarto.dom.Node[], int)" because "refChild.parentNode" is null
      

Get/Post Data:

id = 776348
template = EcEduCourseDetail

Stacktrace:

      
           org.apache.velocity.exception.MethodInvocationException: Invocation of method 'clean' in  class com.insite.infoservis.utils.html.AdvancedHtmlCleaner threw exception class java.lang.NullPointerException : Cannot invoke "jodd.lagarto.dom.Node.insertChild(jodd.lagarto.dom.Node[], int)" because "refChild.parentNode" is null
	at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:232)
	at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:175)
	at org.apache.velocity.runtime.parser.node.ASTReference.render(ASTReference.java:220)
	at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:55)
	at org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:70)
	at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:230)
	at org.apache.velocity.Template.merge(Template.java:256)
	at org.apache.velocity.app.Velocity.mergeTemplate(Velocity.java:449)
rethrown as org.apache.turbine.util.TurbineException: Error rendering Velocity template: screens/EcEduCourseDetail.vm: Invocation of method 'clean' in  class com.insite.infoservis.utils.html.AdvancedHtmlCleaner threw exception class java.lang.NullPointerException : Cannot invoke "jodd.lagarto.dom.Node.insertChild(jodd.lagarto.dom.Node[], int)" because "refChild.parentNode" is null
	at com.insite.infoservis.services.velocity.InfoservisVelocityService.renderingError(InfoservisVelocityService.java:604)
	at com.insite.infoservis.services.velocity.InfoservisVelocityService.decodeRequest(InfoservisVelocityService.java:540)
	at com.insite.infoservis.services.velocity.InfoservisVelocityService.handleRequest(InfoservisVelocityService.java:320)
	at org.apache.turbine.services.velocity.TurbineVelocity.handleRequest(TurbineVelocity.java:110)
	at org.apache.turbine.modules.screens.VelocityScreen.buildTemplate(VelocityScreen.java:151)
	at org.apache.turbine.modules.screens.TemplateScreen.doBuild(TemplateScreen.java:130)
	at org.apache.turbine.modules.Screen.build(Screen.java:99)
	at org.apache.turbine.modules.ScreenLoader.eval(ScreenLoader.java:129)
	at com.insite.nemeton.modules.navigations.DomainAwareTemplateScreen.doRender(DomainAwareTemplateScreen.java:138)
	at com.insite.nemeton.modules.navigations.DomainAwareTemplateScreen.toString(DomainAwareTemplateScreen.java:128)
	at org.apache.velocity.runtime.parser.node.ASTReference.render(ASTReference.java:291)
	at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:55)
	at org.apache.velocity.runtime.parser.node.ASTElseIfStatement.render(ASTElseIfStatement.java:78)
	at org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:89)
	at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:230)
	at org.apache.velocity.Template.merge(Template.java:256)
	at org.apache.velocity.app.Velocity.mergeTemplate(Velocity.java:449)
	at com.insite.infoservis.services.velocity.InfoservisVelocityService.decodeRequest(InfoservisVelocityService.java:537)
	at com.insite.infoservis.services.velocity.InfoservisVelocityService.handleRequest(InfoservisVelocityService.java:320)
	at org.apache.turbine.services.velocity.TurbineVelocity.handleRequest(TurbineVelocity.java:110)
	at com.insite.nemeton.modules.layouts.NemetonVelocityLayout.outputMinimizedScreenContent(NemetonVelocityLayout.java:158)
	at com.insite.nemeton.modules.layouts.NemetonVelocityLayout.doBuild(NemetonVelocityLayout.java:126)
	at org.apache.turbine.modules.Layout.build(Layout.java:91)
	at org.apache.turbine.modules.LayoutLoader.exec(LayoutLoader.java:123)
	at org.apache.turbine.modules.pages.DefaultPage.doBuild(DefaultPage.java:166)
	at org.apache.turbine.modules.Page.build(Page.java:90)
	at org.apache.turbine.modules.PageLoader.exec(PageLoader.java:123)
	at org.apache.turbine.Turbine.doGet(Turbine.java:565)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:529)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:623)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:209)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at cz.educity.stats.filters.StatsLoggingFilter.doFilter(StatsLoggingFilter.java:127)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at cz.educity.tracking.TrackingValidationFilter.doFilter(TrackingValidationFilter.java:69)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:168)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:481)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:130)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:670)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
	at org.apache.coyote.ajp.AjpProcessor.service(AjpProcessor.java:422)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:926)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1790)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.base/java.lang.Thread.run(Thread.java:1583)