Mobile: scroll not working on iOS 8.x and appium 1.3.4 &1.3.6

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    JavascriptExecutor js = (JavascriptExecutor) getDriver();
    HashMap<String, String> scrollObject = new HashMap<String, String>();
    scrollObject.put("direction", "down");
    js.executeScript("mobile: scroll", scrollObject);

I tried above code on native page but seemed the scroll didn’t work on iOS 8.x and appium 1.3.4 &1.3.6 . Any help?