Font Awesome Icon not showing

Hi, the font awesome icon under the feed that links to instagram is not showing – shows a box with a cross through it.

<i class=”fab fa-instagram”></i>

Tried following these instructions: https://docs.blossomthemes.com/seva-lite/general-settings/how-to-configure-social-media-settings/ but I don’t have a “General Settings > Social Media Settings” in my customise screen (Woostify theme)