critical error PHP

My web host has informed me of this error:
 Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function “handle_failed_email” not found or invalid function name in /app/www/wp-includes/class-wp-hook.php:324 Stack trace: #0 /app/www/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(”, Array) #1 /app/www/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #2 /app/www/wp-includes/pluggable.php(581): do_action(‘wp_mail_failed’, Object(WP_Error)) #3 /app/www/wp-content/plugins/forminator/library/abstracts/abstract-class-mail.php(433): wp_mail(Array, ‘Un message de m…’, ‘<p>Mike Martin …’, Array) #4 /app/www/wp-content/plugins/forminator/library/modules/custom-forms/front/front-mail.php(232): Forminator_Mail->send_multiple() #5 /app/www/wp-content/plugins/forminator/library/modules/custom-forms/front/front-action.php(1141): Forminator_CForm_Front_Mail->process_mail(Object(Forminator_Form_Model), Object(Forminator_Form_Entry_Model)) #6 /app/www/wp-content/plugins/forminator/library/modules/custom-forms/front/front-action.php(1123): Forminator_CForm_Front_Action::send_email(Object(Forminator_Form_Entry_Model)) #7 /app/www/wp-content/plugins/forminator/library/abstracts/abstract-class-front-action.php(287): Forminator_CForm_Front_Action->handle_form() #8 /app/www/wp-content/plugins/forminator/library/abstracts/abstract-class-front-action.php(155): Forminator_Front_Action->handle_submit() #9 /app/www/wp-includes/class-wp-hook.php(324): Forminator_Front_Action->maybe_handle_submit(Object(WP)) #10 /app/www/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #11 /app/www/wp-includes/plugin.php(565): WP_Hook->do_action(Array) #12 /app/www/wp-includes/class-wp.php(830): do_action_ref_array(‘wp’, Array) #13 /app/www/wp-includes/functions.php(1336): WP->main(”) #14 /app/www/wp-blog-header.php(16): wp() #15 /app/www/index.php(17): require(‘/app/www/wp-blo…’) #16 {main} thrown.

Can you fix it please ?

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