Fatal error: Uncaught exception 'Facebook\Exceptions\FacebookSDKException' with message 'Required "app_id" key not supplied in config and could not find fallback environment variable "FACEBOOK_APP_ID"' in /var/www/vhosts/optimzaweb.com/httpdocs/core/library/facebook/Facebook.php:139 Stack trace: #0 /var/www/vhosts/optimzaweb.com/httpdocs/core/controllers/facebook.php(38): Facebook\Facebook->__construct(Array) #1 /var/www/vhosts/optimzaweb.com/httpdocs/core/app.php(140): require('/var/www/vhosts...') #2 /var/www/vhosts/optimzaweb.com/httpdocs/index.php(24): require('/var/www/vhosts...') #3 {main} thrown in /var/www/vhosts/optimzaweb.com/httpdocs/core/library/facebook/Facebook.php on line 139