Fatal error: Uncaught Error: Call to undefined function the_field() in /var/www/html/wp-content/themes/mtt/page-templates/free_books.php:40
Stack trace:
#0 /var/www/html/wp-includes/template-loader.php(106): include()
#1 /var/www/html/wp-blog-header.php(19): require_once('...')
#2 /var/www/html/index.php(17): require('...')
#3 {main}
thrown in /var/www/html/wp-content/themes/mtt/page-templates/free_books.php on line 40