Simple Social icons are empty boxes?

Hello!
I just recently noticed that my simple social icons no longer have the social media icon in them. They are just showing up as a colored box depending on what color the background is set to. If the background is set to transparent the boxes don’t show up at all. I have tried changing the colors and sizes and even using a different theme. I went to their plug-in page on WordPress and couldn’t find any answers there either.
On a possibly unrelated note the scroll to top button on my page is also just showing up as a colored circle no matter how I change the colors in my theme.

Website: andlemons.com
Theme: Current is Hello CEO but I also tried it with Hello Sassafras
Any help would be appreciated.