HubSpot Fatal Error

Fatal Error: Uncaught Error: Call to undefined function Leadin\admin\api\wp_json_decode() in /home/site/public_html/wp-content/plugins/leadin/public/admin/modules/api/class-user-meta-api-controller.php:43 Stack trace: #0 /home/site/public_html/wp-includes/rest-api/class-wp-rest-server.php(1292): Leadin\admin\api\User_Meta_Api_Controller->track_consent() #1 /home/site/public_html/wp-includes/rest-api/class-wp-rest-server.php(1125): WP_REST_Server->respond_to_request() #2 /home/site/public_html/wp-includes/rest-api/class-wp-rest-server.php(439): WP_REST_Server->dispatch() #3 /home/site/public_html/wp-includes/rest-api.php(449): WP_REST_Server->serve_request() #4 /home/site/public_html/wp-includes/class-wp-hook.php(324): rest_api_loaded() #5 /home/site/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() #6 /home/site/public_html/wp-includes/plugin.php(565): WP_Hook->do_action() #7 /home/site/public_html/wp-includes/class-wp.php(418): do_action_ref_array() #8 /home/site/public_html/wp-includes/class-wp.php(813): WP->parse_request() #9 /home/site/public_html/wp-includes/functions.php(1336): WP->main() #10 /home/site/public_html/wp-blog-header.php(16): wp() #11 /home/site/public_html/index.php(17): require(‘/home/site/…’) #12 {main} thrown in /home/site/public_html/wp-content/plugins/leadin/public/admin/modules/api/class-user-meta-api-controller.php on line 43