selenium-java解决input标签有readonly无法输入,这个怎么办啊

如图所示
List<WebElement> awardGrade =driver.findElements(By.className("el-input__inner"));
String jsString = "awardGrade.get(5).removeAttribute('readonly')";
((JavascriptExecutor) driver).executeScript(jsString);//执行js去掉readonly属性
awardGrade.get(5).sendKeys("省级");
awardGrade.get(6).sendKeys("一等奖");
出现如下报错
org.openqa.selenium.JavascriptException: javascript error: awardGrade is not defined