This is a terrible side effect of using Divi and another reason I’ll never use 
it again for client websites. 

1. First, disable “Static CSS File Generation under 
Divi Options > Builder > Advanced.

2. Next, delete the ET Cache Folder either in File Manager or via FTP. 

3. Lastly, edit your wp-config.php file by adding this line: 
define( ‘ET_BUILDER_CACHE_MODULES’, false );