Not sending

Hi, I get this error by email when trying to send mail. Email is not sent as reported previously here. Perhaps this helps.

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Tiedoston /var/www/vhosts/mysite/httpdocs/wp-content/plugins/wp-email-users/wp-send-mail.php rivill? 1003 havaittiin virhe lajia E_ERROR. Virheviesti: Uncaught Error: Call to undefined function tsweu_isUnsubscribe() in /var/www/vhosts/mysite/httpdocs/wp-content/plugins/wp-email-users/wp-send-mail.php:1003
Stack trace:
#0 /var/www/vhosts/mysite/httpdocs/wp-includes/class-wp-hook.php(287): tsweu_admin_page(”)
#1 /var/www/vhosts/mysite/httpdocs/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(”, Array)
#2 /var/www/vhosts/mysite/httpdocs/wp-includes/plugin.php(484): WP_Hook->do_action(Array)
#3 /var/www/vhosts/mysite/httpdocs/wp-admin/admin.php(259): do_action(‘wp-email-users_…’)
#4 {main}
thrown