Note: There may be a  long file like httpd.conf that may contain your domain's  configuration.

Edit your domain configuration;

pico /etc/apache2/sites-available/doc_root

Set the Overide for your domain configuration
Paste with your path;

<Directory "/home/user_name/www/public_html/domain">
 AllowOverride All
</Directory>

Then;
Cntl+X
Y
enterkey

Then restart the Apache server