Errors with plugin

Hello,
Recently I started using this plugin and noticed that it generates errors for some reason. Here is what I get:

In the “Last records” section it’s always the same one:
Warning: Trying to access array offset on value of type bool in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/views/send-pdf-admin.php on line 1395

And when I export those to a CSV, I get more detailed errors:
Warning: Undefined variable $_SESSION in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 413
Warning: Trying to access array offset on value of type null in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 413
Warning: Trying to access array offset on value of type bool in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 1586
Warning: foreach() argument must be of type array|object, bool given in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 1587
Warning: Trying to access array offset on value of type bool in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 1586
Warning: foreach() argument must be of type array|object, bool given in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 1587
Warning: Trying to access array offset on value of type bool in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 1586
Warning: foreach() argument must be of type array|object, bool given in <…>/public_html/wp-content/plugins/send-pdf-for-contact-form-7/classes/send-pdf.php on line 1587