Error after last update

Hi,

PDF for Contact Form 7 + Drag and Drop Template Builder worked until the last update (6.5.1).
After the update no mails are sent after the creation of the PDF and in the logs I see this error:

Un errore di E_ERROR è stato causato nella linea 443 del file /var/www/******/wp-content/plugins/pdf-for-contact-form-7/backend/index.php. Messaggio di errore: Uncaught Error: Class "Mpdf\Config\ConfigVariables" not found in /var/www/******/wp-content/plugins/pdf-for-contact-form-7/backend/index.php:443 Stack trace: #0 /var/www/******/wp-includes/class-wp-hook.php(341): Yeepdf_Settings_Builder_PDF_Backend->add_font() #1 /var/www/******/wp-includes/class-wp-hook.php(365): WP_Hook->apply_filters() #2 /var/www/******/wp-includes/plugin.php(522): WP_Hook->do_action() #3 /var/www/******/wp-admin/admin-header.php(168): do_action() #4 /var/www/******/wp-admin/edit.php(411): require_once('...') #5 {main} thrown

My wordpress version is 6.9.1 with PHP 8.3.30

Could you help me, please?
Salvo