Why do I get an error message when I click on the activation link?

Hi, I’ve getting the following error when a user clicks the email verification link. (and the verification does not work). Any ideas?

An unexpected fatal error occurred on the site.
Fatal error: Uncaught Error: Class ‘WC_Email’ not found in /home/customer/www/codeben.com/public_html/wp-content/plugins/email-verification-for-woocommerce-pro/includes/pro/class-alg-wc-ev-pro.php:412
Stack trace:
#0 /home/customer/www/codeben.com/public_html/wp-includes/class-wp-hook.php(287): Alg_WC_Email_Verification_Pro->maybe_add_wc_email_style(‘Por favor cliqu…’, ‘mail’)
#1 /home/customer/www/codeben.com/public_html/wp-includes/plugin.php(206): WP_Hook->apply_filters(‘Por favor cliqu…’, Array)
#2 /home/customer/www/codeben.com/public_html/wp-content/plugins/email-verification-for-woocommerce-pro/includes/class-alg-wc-ev-emails.php(178): apply_filters(‘alg_wc_ev_send_…’, ‘Por favor cliqu…’, ‘mail’)
#3 /home/customer/www/codeben.com/public_html/wp-content/plugins/email-verification-for-woocommerce-pro/includes/class-alg-wc-ev-emails.php(121): Alg_WC_Email_Verification_Emails->send_mail(‘xxxxxxxxxx@…’, ‘Por favor ative…’, ‘Por favor cliqu…’)
#4 /home/customer/www/codeben.com/public_html/wp-content/plu in /home/customer/www/codeben.com/public_html/wp-content/plugins/email-verification-for-woocommerce-pro/includes/pro/class-alg-wc-ev-pro.php on line 412