IWDWindow do not get destroy completely!!!! Please Help

I Created a IWDwindow, when i close it, the window does not get closed completely leaving a tiny small area on the screen, as it's modal, i cant do anything else. anyone know why?

here's how i create the IWDWindow

try {
                        IWDWindowInfo windowInfo = (IWDWindowInfo)wdComponentAPI.getComponentInfo().findInWindows("ErrorPopupWin");
                        
                        IWDWindow window = this.wdComponentAPI.getWindowManager().createModalWindow(windowInfo);
                        wdContext.currentContextElement().setErrorWindowInstance(window); 
                           
                        window.setWindowPosition(WDWindowPos.CENTER);
                              
                        window.show();
                           
                        Thread.sleep(100);
                        
                     } catch (InterruptedException e) {
                           e.printStackTrace();
                     }

and here's how i close it

wdContext.currentContextElement().getErrorWindowInstance().destroyInstance();