Light fonts not appearing on site

I've created a new project and added a bunch of fonts (Sofia Pro) to it (including bold, normal ande light font weights). Adobe Fonts has generated a CSS file and I have included it in my site's header. It works, but I cannot seem to be able to use light fonts.

Eg:

font-weight: 100;

 doesnt work, but 

font-weight: 700;

does.

Would anyone know how I can fix this?