Uncaught Exception

Error: Call to undefined method SimpleSAML\Session::getInstance() in /srv/sites/one/www/lib/_helpers.php:1179
Stack trace:
#0 /srv/sites/one/www/app/controller.php(115): _getGlobalLoginMethod()
#1 /srv/sites/one/www/app/controller/base.php(55): App\Controller->getRedirect(Array, Array)
#2 /srv/sites/one/www/app/controller.php(109): App\Controller\Base->handle('GET', Array, Array, Array)
#3 /srv/sites/one/www/app/Router.php(58): App\Controller->handle('GET', Array, Array, Array)
#4 {main}