It looks like something is not set up correctly on your server or at least in that directory. I see index.php files in both synergies.co.za/blog/ and synergies.co.za/blog/wp-admin/.
Using either your hosts File Manager or an FTP program, double check for the .htaccess file. It's a hidden file, so you will need to make sure you have selected the option to view hidden files. If you do have an .htaccess file, open the file and see if you see any reference to DirectoryIndex (followed by a filename). If you do see that, and the file name after it is anything other than index.php, remove that line.
It really looks like something is going on with that site URL. You should double check your wp-config.php file and functions.php to see if the site url has been changed in either of those files. Additionally, if you have set the site url correctly in the database:
Also, when I use PHPMyAdmin the site URL is listed as http://www.synergies.co.za/blog which is the correct location.
You do NOT need to use any of the other methods for changing the site URL. The Relocate Method is not needed so you will want to remove that. Have you confirmed that both the siteurl and home fields in your database are set to http://www.synergies.co.za/blog?
Hope this helps!