Fatal error: Uncaught Error: Call to undefined function sanitize_text_field() in /home3/mercatri/public_html/wp-content/plugins/tutor-pro/addons/gradebook/views/pages/grade_book.php:4 Stack trace: #0 {main} thrown in /home3/mercatri/public_html/wp-content/plugins/tutor-pro/addons/gradebook/views/pages/grade_book.php on line 4