please connect to Facebook to interact and post

Notice: Undefined variable: sPageId in /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/guestbookEntries.php on line 48

Fatal error: Uncaught exception 'Facebook\Exceptions\FacebookAuthenticationException' with message 'No node specified' in /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/vendor/Facebook/Exceptions/FacebookResponseException.php:100 Stack trace: #0 /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/vendor/Facebook/FacebookResponse.php(210): Facebook\Exceptions\FacebookResponseException::create(Object(Facebook\FacebookResponse)) #1 /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/vendor/Facebook/FacebookResponse.php(255): Facebook\FacebookResponse->makeException() #2 /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/vendor/Facebook/FacebookResponse.php(82): Facebook\FacebookResponse->decodeBody() #3 /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/vendor/Facebook/FacebookClient.php(225): Facebook\FacebookResponse->__construct(Object(Facebook\FacebookRequest), '{"error":{"mess...', 400, Array) #4 /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/vendor/Facebook/Facebook.php(504): Facebook\FacebookClient->sendRequest( in /var/www/vhosts/hostel-service.de/httpdocs/apps/fb/vendor/Facebook/Exceptions/FacebookResponseException.php on line 100