The primary contact for safety issues is the police (phone number 110). The youth welfare department: https://www.kinderinfo.de/jugendaemter/nordrhein-westfalen/
the Centers for Child protection: http://www.kinderschutz-in-nrw.de/fuer-fachkraefte/kinderschutz-in-nrw/kinderschutz-zentren.html
the Emergency service for children and youngster https://hast-du-stress.de/krisentelefone-regional-beratungsstellen-fuer-kinder-und-jugendliche-in-not/