Be sure that your theme is up to date. When Divi updated, Josefin version 2.0 and later stopped working due to some customizations on Elegant Theme's side.
To fix this issue:
1) Make sure Josefin is updated to the most recent version
2) Make sure the following script is inserted in the "Divi > Theme Options > Integration > Header" section. Also, make sure the "enable header code" toggle is on:
Still not seeing the changes? Make sure you purge your cache and hard refresh.