Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, no array or string given in /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php:324 Stack trace: #0 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/plugin.php(205): WP_Hook->apply_filters(2700000, Array) #1 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/class-wp-session.php(141): apply_filters('_rfqtk_wp_sessi...', 2700000) #2 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/class-wp-session.php(165): RFQTK_WP_Session->set_expiration() #3 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/class-wp-session.php(125): RFQTK_WP_Session->set_cookie() #4 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/class-wp-session.php(72): RFQTK_WP_Session->__construct() #5 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/wp-session.php(86): RFQTK_WP_Session::get_instance() #6 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php(324): RFQTK_wp_session_start('') #7 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #8 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #9 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-settings.php(559): do_action('plugins_loaded') #10 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-config.php(78): require_once('/home/httpd/vho...') #11 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-load.php(50): require_once('/home/httpd/vho...') #12 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-blog-header.php(13): require_once('/home/httpd/vho...') #13 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/index.php(17): require('/home/httpd/vho...') #14 {main} thrown in /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php on line 324 Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, no array or string given in /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php:324 Stack trace: #0 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/plugin.php(205): WP_Hook->apply_filters(2700000, Array) #1 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/class-wp-session.php(141): apply_filters('_rfqtk_wp_sessi...', 2700000) #2 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/class-wp-session.php(126): RFQTK_WP_Session->set_expiration() #3 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/class-wp-session.php(72): RFQTK_WP_Session->__construct() #4 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-content/plugins/woo-rfq-for-woocommerce/wp-session-manager/includes/wp-session.php(127): RFQTK_WP_Session::get_instance() #5 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php(324): RFQTK_wp_session_write_close('') #6 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #7 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #8 /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/load.php(1279): do_action('shutdown') #9 [internal function]: shutdown_action_hook() #10 {main} thrown in /home/httpd/vhosts/powerstation-eventtechnik.ch/httpdocs/wp-includes/class-wp-hook.php on line 324