org.openqa.selenium.WebDriverException：[Exception ...“Component is not available”nsresult：“0x80040111（NS_ERROR_NOT_AVAILABLE）”

Question

@Test
public void Workflowstatus() throws Exception {

        guitils.loginToPortal(userName1, password1, driver);
        guitils.LightiningView(driver);
        driver.findElement(By.linkText("ICIX")).click();
        Thread.sleep(3000);
        // TP Group 1
        TPO.create_tpGroup(driver, Group);
        Thread.sleep(8000);
        driver.findElement(By.linkText(Group)).click();
        Thread.sleep(8000);
        // set requirements 1
        driver.findElement(By.linkText("Set Requirements")).click();
        Thread.sleep(3000);
        driver.switchTo().frame(driver.findElement(By.id("vfFrameId")));
        Thread.sleep(3000);
}

我在代码中提到的“组”链接上遇到了提及错误。 有时代码工作得很好，有时却不是

有人请做必要的。万分感谢