Unfortunately, we didn’t find the supsystic slider on this page. Can you please, check if the plugin is made by supsystic or if is it on this page?
At least, if everything is right – please, provide the screenshot with an area – where the plugin – Slider by Supsystic is.
If i didn’t understand you clearly at the first paragraph, your shortcode isn’t generated? Please, show us the admin panel screenshot where is the shortcode field empty