Fatal error: Uncaught TypeError: Argument 1 passed to DBWorkDozenten::getDozenten4KursWB() must be of the type string, null given, called in /home/www/relaunch2018/fileadmin/kuferweb/classes/export/ExportCalculation.php on line 2170 and defined in /home/www/relaunch2018/fileadmin/kuferweb/classes/db/DBWorkDozenten.php:1298 Stack trace: #0 /home/www/relaunch2018/fileadmin/kuferweb/classes/export/ExportCalculation.php(2170): DBWorkDozenten->getDozenten4KursWB(NULL) #1 /home/www/relaunch2018/fileadmin/kuferweb/classes/export/ExportKursuebersicht.php(41): ExportCalculation->getVarValue4Kurs('doz_1_vorname', Object(Kurs)) #2 /home/www/relaunch2018/fileadmin/kuferweb/classes/exportadapter/Exportadapter.php(432): ExportKursuebersicht->getVarValue('k_doz_1_vorname') #3 /home/www/relaunch2018/fileadmin/kuferweb/classes/exportadapter/Exportadapter.php(92): Exportadapter->fillVarsByVariableList('\n\n<table cellpa...', Array) #4 /home/www/relaunch2018/fileadmin/kuferweb/classes/exportadapter/Exportadapter.php(564): Exportadapter->fil in /home/www/relaunch2018/fileadmin/kuferweb/classes/db/DBWorkDozenten.php on line 1298