AddThis Social Sharing Plugin

Hi. I've had a quick look in the community forums but couldn't find anything specifically for a plug in that I'm using. I'm using Add This, the social sharing buttons plug in. I've installed it, set it up, and added it to my blog posts via the drag and drop feature in Up Front. However, the sharing buttons fail to appear. Is this an issue you're aware of? Is there anyone who can hep me fix this issue?