wpra error

i saw this thread:
https://www.ads-software.com/support/topic/wordpress-site-crash-with-wp-rss-aggregator-4-15-1/

and it seems you have this error again, i started seeing on my wordpress this error:

WP RSS Aggregator has encountered an error. If this problem persists, kindly contact customer support and provide the following details:
Click to show error details
Error Message:

Class 'RebelCode\Wpra\Core\Modules\UpsellModule' not found (wp-content/plugins/wp-rss-aggregator/wp-rss-aggregator.php:416)

Stack trace:

#0 /opt/bitnami/apps/wordpress/htdocs/wp-content/plugins/wp-rss-aggregator/wp-rss-aggregator.php(373): wpra_modules()
#1 /opt/bitnami/apps/wordpress/htdocs/wp-content/plugins/wp-rss-aggregator/wp-rss-aggregator.php(348): wpra()
#2 /opt/bitnami/apps/wordpress/htdocs/wp-includes/class-wp-hook.php(286): wpra_run('')
#3 /opt/bitnami/apps/wordpress/htdocs/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL, Array)
#4 /opt/bitnami/apps/wordpress/htdocs/wp-includes/plugin.php(465): WP_Hook->do_action(Array)
#5 /opt/bitnami/apps/wordpress/htdocs/wp-settings.php(394): do_action('plugins_loaded')
#6 /opt/bitnami/apps/wordpress/htdocs/wp-config.php(124): require_once('/opt/bitnami/ap...')
#7 /opt/bitnami/apps/wordpress/htdocs/wp-load.php(37): require_once('/opt/bitnami/ap...')
#8 /opt/bitnami/apps/wordpress/htdocs/wp-admin/admin.php(34): require_once('/opt/bitnami/ap...')
#9 /opt/bitnami/apps/wordpress/htdocs/wp-admin/index.php(10): require_once('/opt/bitnami/ap...')

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