Website load Fallback Fonts instead of my defined Fonts

Hi,

i build a newsletter but the site load always the fallback fonts. In Webflow it work well.

But when i self host the site, it does not work. Only when i manuel delete in the code the second font. Then it work.

This code does not work:
font-family: Footlight, sans-serif;

I delete sans-serif and it work:
font-family: Footlight;