I was troubleshooting the issue on your site but as i don’t have your site FTP details so i was making changes from wp editor which caused Internal server error on your site.
Could you please resolve it by resetting htaccess file as described on the following pages?
http://www.bordercrossingmedia.com/2009/01/how-to-restore-your-wordpress-htaccess-file/
https://www.webhostinghero.com/restore-damaged-htaccess-file-wordpress/