Notice (8): Undefined variable: row [APP/View/Elements/header.php, line 20]

Fatal error: Uncaught TypeError: Argument 1 passed to Hash::get() must be of the type array, null given, called in /var/www/vhosts/schillathoehle.de/httpdocs/View/Elements/header.php on line 20 and defined in /var/www/vhosts/schillathoehle.de/httpdocs/contrance/Vendor/Cake/lib/Cake/Utility/Hash.php:45 Stack trace: #0 /var/www/vhosts/schillathoehle.de/httpdocs/View/Elements/header.php(20): Hash::get(NULL, 'HeaderImagesMed...') #1 /var/www/vhosts/schillathoehle.de/httpdocs/contrance/Vendor/Cake/lib/Cake/View/View.php(971): include('/var/www/vhosts...') #2 /var/www/vhosts/schillathoehle.de/httpdocs/contrance/Vendor/Cake/lib/Cake/View/View.php(933): View->_evaluate('/var/www/vhosts...', Array) #3 /var/www/vhosts/schillathoehle.de/httpdocs/contrance/Vendor/Cake/lib/Cake/View/View.php(1224): View->_render('/var/www/vhosts...', Array) #4 /var/www/vhosts/schillathoehle.de/httpdocs/contrance/Vendor/Cake/lib/Cake/View/View.php(418): View->_renderElement('/var/www/vhosts...', Array, Array) #5 /var/www/vhosts/schillathoehle.de/httpdo in /var/www/vhosts/schillathoehle.de/httpdocs/contrance/Vendor/Cake/lib/Cake/Utility/Hash.php on line 45