Icon won’t appear

I’ve used the plugin to add icons to my homepage. However, in trying to add an address card icon to the About us page, I cannot get it to appear. I’ve copied icons from the homepage and gotten them to appear in the location I am working on. I have also been using the short code that I have used successfully on other sites (as recently as this morning). [icon name=”address-card-o” class=”” unprefixed_class=””] I have no idea why this particular page is having an issue with it. Any suggestions?

The page I need help with: [log in to see the link]