Custom CSS code suddenly not working

I finished a client's website a few weeks ago, and now suddenly the custom fonts are showing as Times New Roman. Neither of us touched the CSS so I have no idea what went wrong. For reference:

@font-face {

    font-family: 'Belleza-Regular';

       src: url('https://static1.squarespace.com/static/641b592dad71542d89141fcd/t/641c98e8858d441d4a2c0c8c/1679595753009/Belleza-Regular.ttf');

  }

h3 {font-family: 'Belleza-Regular';}
h4 {font-family: 'Belleza-Regular';}

@font-face {

    font-family: 'Summer Pisces';

       src: url('https://static1.squarespace.com/static/641b592dad71542d89141fcd/t/641cec92fe462d54140a49b2/1679617170858/Summer+Pisces.otf');

  }

h1 {font-family: 'Summer Pisces';}
h2 {font-family: 'Summer Pisces';}

Please post the URL for a page on your site where we can see your issue.

A link to the backend of the your site won’t work for us, i.e. a url that contains /config/.

Please set up a site-wide password, if your site is not public and you've not already done so.

Post the password here.

Adding a site-wide password does not allow anyone to alter your site. It only allows those with the password to see your site.

Please read the site-wide password and how to share a link documentation to understand how they work.

We can then take a look at your issue.

You may find How to post a forum question post useful.

Sorry, totally thought I added the URL!

https://www.kaciandcowellness.com

YOU ARE A LIFE SAVER. Thank you so so much!

Thinking more on this... if the original site was deleted, why should that matter considering I downloaded the file to my computer? The original site shouldn't matter at that point, no? Maybe I'm misunderstanding. I'm learning!

Quote

if the original site was deleted, why should that matter considering I downloaded the file to my computer?

The fonts need to be available somewhere on the internet at a URL the site can reach to use the files.

If the files are on your computer, the website can't reach them. You need to upload them to the current site and fix the URLs in your CSS rulesets.