Why did I start getting file conversion errors relating to fonts not being available in my database?

Starting around the middle of June 2023, we started getting font conversion errors, indicating that a font was not in our database when converting the file to .pdf.  It had to choose a similar font.  Why did it start getting this error at this time.  We have been using Collaborator Enterprise (v13.6) since June of 2021.  What triggered this change?  Why did we start getting this error after two years of use?

I can put the same document in our test server that is using v14.3, and the conversion happens just fine.  I could see us having a problem the whole time we have been using v13.6, but why did we start having problems after 2 years of use?

Other than upgrading, what can we do to add different fonts to our database?