Fatal error: Uncaught TypeError: Return value of NF_Admin_Metaboxes_Calculations::registerReactMetabox() must be an instance of void, none returned in /homepages/31/d431851588/htdocs/clickandbuilds/bitcoin4card/wp-content/plugins/ninja-forms/includes/Admin/Metaboxes/Calculations.php:37 Stack trace: #0 /homepages/31/d431851588/htdocs/clickandbuilds/bitcoin4card/wp-content/plugins/ninja-forms/includes/Admin/Metaboxes/Calculations.php(7): NF_Admin_Metaboxes_Calculations->registerReactMetabox() #1 /homepages/31/d431851588/htdocs/clickandbuilds/bitcoin4card/wp-content/plugins/ninja-forms/ninja-forms.php(370): NF_Admin_Metaboxes_Calculations->__construct() #2 /homepages/31/d431851588/htdocs/clickandbuilds/bitcoin4card/wp-content/plugins/ninja-forms/ninja-forms.php(1227): Ninja_Forms::instance() #3 /homepages/31/d431851588/htdocs/clickandbuilds/bitcoin4card/wp-content/plugins/ninja-forms/ninja-forms.php(1230): Ninja_Forms() #4 /homepages/31/d431851588/htdocs/clickandbuilds/bitcoin4card/wp-settings.php(418): include_once('/homepa in /homepages/31/d431851588/htdocs/clickandbuilds/bitcoin4card/wp-content/plugins/ninja-forms/includes/Admin/Metaboxes/Calculations.php on line 37