components inside static layout container component is not showing up in content tree

Hi 

I have created a static component with two responsive grids like below(6/6)

<div class="aem-Grid aem-Grid--12">
    <div class="aem-GridColumn aem-GridColumn--default--6">
        <sly data-sly-resource="${'grid6-1' @resourceType='wcm/foundation/components/responsivegrid'}"></sly>

    </div>
    <div class="aem-GridColumn aem-GridColumn--default--6">
        <sly data-sly-resource="${'grid6-2' @resourceType='wcm/foundation/components/responsivegrid'}"></sly>

    </div>

</div>

 so when I drag and drop some components(in beloweg:headline) inside this 6 column(in below eg: layout-6-6)  container it is not showing the content tree However it is creating separate thread and showing there. Any Idea what could be the reason