Fatal error: Uncaught Error: Call to undefined function AffiliateWP\Admin\Affiliates\Groups\Meta\untrailingslashit() in /home/adaptyo3/public_html/wp-content/plugins/affiliate-wp/includes/admin/affiliates/groups/meta/trait-flat-rate-basis.php:21 Stack trace: #0 {main} thrown in /home/adaptyo3/public_html/wp-content/plugins/affiliate-wp/includes/admin/affiliates/groups/meta/trait-flat-rate-basis.php on line 21