Fatal error: Uncaught TypeError: Return value of NF_Admin_Metaboxes_Calculations::registerReactMetabox() must be an instance of void, none returned in /homepages/34/d195460062/htdocs/clickandbuilds/AmantiiTEST/Amantii-Test-2017-05/wp-content/plugins/ninja-forms/includes/Admin/Metaboxes/Calculations.php:37 Stack trace: #0 /homepages/34/d195460062/htdocs/clickandbuilds/AmantiiTEST/Amantii-Test-2017-05/wp-content/plugins/ninja-forms/includes/Admin/Metaboxes/Calculations.php(7): NF_Admin_Metaboxes_Calculations->registerReactMetabox() #1 /homepages/34/d195460062/htdocs/clickandbuilds/AmantiiTEST/Amantii-Test-2017-05/wp-content/plugins/ninja-forms/ninja-forms.php(375): NF_Admin_Metaboxes_Calculations->__construct() #2 /homepages/34/d195460062/htdocs/clickandbuilds/AmantiiTEST/Amantii-Test-2017-05/wp-content/plugins/ninja-forms/ninja-forms.php(1237): Ninja_Forms::instance() #3 /homepages/34/d195460062/htdocs/clickandbuilds/AmantiiTEST/Amantii-Test-2017-05/wp-content/plugins/ninja-forms/ninja-forms.php(1240): Ninja_Forms() #4 /ho in /homepages/34/d195460062/htdocs/clickandbuilds/AmantiiTEST/Amantii-Test-2017-05/wp-content/plugins/ninja-forms/includes/Admin/Metaboxes/Calculations.php on line 37