I checked your website, chrome and edge normally show the icons in my browsers. I think you have extension which makes conflict with the icons, or it may be a cache problem, also try cleaning the browser caches.

Im very new to web design, trying to learn as I go, I use a Mac, however just testing the site on different browsers, I noticed the icons don't show up on Firefox, edge, and chrome, for some reason they only show up on safari and iOS perfectly fine. not sure if someone can guide me on how to fix this issue? 

thanks