Fatal Error Bulk Download PDF Invoice

I receive a fatal error when try apply Bulk Download PDF Invoice, i tried to reduce the number of orders to max 10 but always error. This is the error details:

Dettagli dell'errore
====================
Un errore di E_ERROR è stato causato nella linea 616 del file /home/xtdimora/public_html/wp-content/plugins/pepro-ultimate-invoice/include/admin/class-print.php. Messaggio di errore: Uncaught Error: Call to a member function get_price() on bool in /home/xtdimora/public_html/wp-content/plugins/pepro-ultimate-invoice/include/admin/class-print.php:616
Stack trace:
#0 /home/xtdimora/public_html/wp-content/plugins/pepro-ultimate-invoice/include/admin/class-print.php(857): peproulitmateinvoice\PeproUltimateInvoice_Print->create_html('47311', 'PDF', '', '', true)
#1 /home/xtdimora/public_html/wp-content/plugins/pepro-ultimate-invoice/pepro-ultimate-invoice.php(413): peproulitmateinvoice\PeproUltimateInvoice_Print->create_pdf('47311', false, 'S')
#2 /home/xtdimora/public_html/wp-includes/class-wp-hook.php(303): peproulitmateinvoice\PeproUltimateInvoice->init_plugin('')
#3 /home/xtdimora/public_html/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters(NULL, Array)
#4 /home/xtdimora/public_html/wp-includes/plugin.php(470): WP_Hook->do_action(Array)
#5 /home/xtdimora/public_html/wp-settings.php(578): do_action('init')
#6 /home/xtdimora/public_html/wp-config.php(191): require_once('/home/xtdimo

Hope you can help me because I like this plugin and would put five stars review when solved this issue. Thank You

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