320 px size ad size how to put on right sidebar

To use Ads size 320px into right sidebar, you can do as the following: 
– Add the following code to the style.css file:
#sidebar-secondary {
    width: 320px;
}

@media only screen and (max-width: 1024px) {
   #sidebar-secondary {
      width: 100% !important;
  }
}
– Log in to Dashboard > widget, Add “Text” widget to the Secondary sidebar, then add the following code to the Text widget:
<a href=”Your Link” class=”text-ads”><img src=”URL LINK“></a>
Note: You can upload your image into Media and copy the URL link then change into above link.
See the screenshot: http://prntscr.com/63owao
If you still face there issue, please send me your site for further checking.
Hope this helps !