Plugin create Fatal error

I can’t edit a existing campaign on one of my clients sites. WP send me this “fatal error report” to me as admin.
Uppgifter om felet
==================
Ett fel av typen E_ERROR uppstod p? rad 509 i f?ljande fil: /storage/content/30/196630/oceaniaacademy.com/public_html/wp-content/plugins/newsletter-manager/admin/edit_campaign.php. Felorsak: Uncaught Error: Call to undefined function ecs_attr() in /storage/content/30/196630/oceaniaacademy.com/public_html/wp-content/plugins/newsletter-manager/admin/edit_campaign.php:509
Stack trace:
#0 /storage/content/30/196630/oceaniaacademy.com/public_html/wp-content/plugins/newsletter-manager/admin/menu.php(269): include()
#1 /storage/content/30/196630/oceaniaacademy.com/public_html/wp-includes/class-wp-hook.php(288): em_manage_campaigns(”)
#2 /storage/content/30/196630/oceaniaacademy.com/public_html/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters(”, Array)
#3 /storage/content/30/196630/oceaniaacademy.com/public_html/wp-includes/plugin.php(478): WP_Hook->do_action(Array)
#4 /storage/content/30/196630/oceaniaacademy.com/public_html/wp-admin/admin.php(254): do_action(‘xyz-newsletter_…’)
#5 {main}
thrown

So it says error on line 509 in: …/newsletter-manager/admin/edit_campaign.php

Error cause: Uncaught Error: Call to undefined function ecs_attr() in /storage/content/30/196630/oceaniaacademy.com/public_html/wp-content/plugins/newsletter-manager/admin/edit_campaign.php:509

And on another client site the sending out newsletter stopped after 249 (has 2000 left to send but stoped), and I get a “fatal error” from WP in my admin mail:

Uppgifter om felet
==================
Ett fel av typen E_ERROR uppstod p? rad 509 i f?ljande fil: /var/www/vhosts/starsofbeauty.se/httpdocs/wp-content/plugins/newsletter-manager/admin/edit_campaign.php. Felorsak: Uncaught Error: Call to undefined function ecs_attr() in /var/www/vhosts/starsofbeauty.se/httpdocs/wp-content/plugins/newsletter-manager/admin/edit_campaign.php:509
Stack trace:
#0 /var/www/vhosts/starsofbeauty.se/httpdocs/wp-content/plugins/newsletter-manager/admin/menu.php(269): include()
#1 /var/www/vhosts/starsofbeauty.se/httpdocs/wp-includes/class-wp-hook.php(286): em_manage_campaigns(”)
#2 /var/www/vhosts/starsofbeauty.se/httpdocs/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(”, Array)
#3 /var/www/vhosts/starsofbeauty.se/httpdocs/wp-includes/plugin.php(465): WP_Hook->do_action(Array)
#4 /var/www/vhosts/starsofbeauty.se/httpdocs/wp-admin/admin.php(253): do_action(‘xyz-newsletter_…’)
#5 {main}
thrown

I hope there is a update/fix on the way so this excelent plugin can continue to work as goos as it has for many years ??

Thanks in advance!
// Roger

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