Error message

• Warning: include(sitemap.php): failed to open stream: No such file or directory in eval() (line 1 of /var/www/vhosts/muddlebridge.co.uk/httpdocs/modules/php/php.module(80) : eval()'d code).
• Warning: include(sitemap.php): failed to open stream: No such file or directory in eval() (line 1 of /var/www/vhosts/muddlebridge.co.uk/httpdocs/modules/php/php.module(80) : eval()'d code).
• Warning: include(): Failed opening 'sitemap.php' for inclusion (include_path='.:/opt/plesk/php/5.6/share/pear') in eval() (line 1 of /var/www/vhosts/muddlebridge.co.uk/httpdocs/modules/php/php.module(80) : eval()'d code).