Warning: Undefined variable $empty in /var/www/www.cabaretinfo.nl/live/includes/include.php on line 504

Fatal error: Uncaught Error: Value of type null is not callable in /var/www/www.cabaretinfo.nl/live/includes/include.php:504
Stack trace:
#0 /var/www/www.cabaretinfo.nl/live/includes/include.php(74): Cabaretinfo\getMetaInfo(Object(Cabaretinfo\PDO_DB))
#1 /var/www/www.cabaretinfo.nl/live/html/city_detail.php(6): require_once('/var/www/www.ca...')
#2 {main}
  thrown in /var/www/www.cabaretinfo.nl/live/includes/include.php on line 504