Fatal error: Uncaught TypeError: JTL\Shop::setLanguage(): Argument #1 ($languageID) must be of type int, null given, called in /var/www/virtual/lassners-schulzeit.de/htdocs/includes/src/Session/Frontend.php on line 321 and defined in /var/www/virtual/lassners-schulzeit.de/htdocs/includes/src/Shop.php:355
Stack trace:
#0 /var/www/virtual/lassners-schulzeit.de/htdocs/includes/src/Session/Frontend.php(321): JTL\Shop::setLanguage()
#1 /var/www/virtual/lassners-schulzeit.de/htdocs/includes/src/Session/Frontend.php(117): JTL\Session\Frontend->updateGlobals()
#2 /var/www/virtual/lassners-schulzeit.de/htdocs/includes/src/Session/Frontend.php(75): JTL\Session\Frontend->setStandardSessionVars()
#3 /var/www/virtual/lassners-schulzeit.de/htdocs/includes/src/Session/Frontend.php(61): JTL\Session\Frontend->__construct()
#4 /var/www/virtual/lassners-schulzeit.de/htdocs/includes/globalinclude.php(96): JTL\Session\Frontend::getInstance()
#5 /var/www/virtual/lassners-schulzeit.de/htdocs/index.php(5): require('...')
#6 {main}
thrown in /var/www/virtual/lassners-schulzeit.de/htdocs/includes/src/Shop.php on line 355