Unexpected exception?

[LeoTRBL]

javafx.fxml.LoadException: 
file:/C:/Users/phuong/Downloads/BetonQuest-Editor.jar!/pl/betoncraft/betonquest/editor/view/tab/ConversationTab.fxml:37
file:/C:/Users/phuong/Downloads/BetonQuest-Editor.jar!/pl/betoncraft/betonquest/editor/view/Tabs.fxml:10
file:/C:/Users/phuong/Downloads/BetonQuest-Editor.jar!/pl/betoncraft/betonquest/editor/view/Root.fxml:22

	at javafx.fxml.FXMLLoader.constructLoadException(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.access$2700(Unknown Source)
	at javafx.fxml.FXMLLoader$IncludeElement.constructValue(Unknown Source)
	at javafx.fxml.FXMLLoader$ValueElement.processStartElement(Unknown Source)
	at javafx.fxml.FXMLLoader.processStartElement(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.access$2700(Unknown Source)
	at javafx.fxml.FXMLLoader$IncludeElement.constructValue(Unknown Source)
	at javafx.fxml.FXMLLoader$ValueElement.processStartElement(Unknown Source)
	at javafx.fxml.FXMLLoader.processStartElement(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
	at javafx.fxml.FXMLLoader.load(Unknown Source)
	at pl.betoncraft.betonquest.editor.BetonQuestEditor.start(BetonQuestEditor.java:112)
	at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$159(Unknown Source)
	at com.sun.javafx.application.LauncherImpl$$Lambda$53/11484101.run(Unknown Source)
	at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$172(Unknown Source)
	at com.sun.javafx.application.PlatformImpl$$Lambda$46/20085625.run(Unknown Source)
	at com.sun.javafx.application.PlatformImpl.lambda$null$170(Unknown Source)
	at com.sun.javafx.application.PlatformImpl$$Lambda$48/20762068.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at com.sun.javafx.application.PlatformImpl.lambda$runLater$171(Unknown Source)
	at com.sun.javafx.application.PlatformImpl$$Lambda$47/2900468.run(Unknown Source)
	at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
	at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
	at com.sun.glass.ui.win.WinApplication.lambda$null$145(Unknown Source)
	at com.sun.glass.ui.win.WinApplication$$Lambda$36/17230114.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.UnsupportedOperationException: Cannot determine type for property.
	at com.sun.javafx.fxml.BeanAdapter.getSetterMethod(Unknown Source)
	at com.sun.javafx.fxml.BeanAdapter.put(Unknown Source)
	at javafx.fxml.FXMLLoader$Element.processEventHandlerAttributes(Unknown Source)
	at javafx.fxml.FXMLLoader$ValueElement.processEndElement(Unknown Source)
	at javafx.fxml.FXMLLoader.processEndElement(Unknown Source)
	... 30 more