Hi @spielzeugfuchs
Have you received any support or solution to this error? I just installed the plugin and as soon as I try to create a new feed I get the same error, also no email.
May I ask you what PHP version your website is running, Woocommerce and WordPress version? I’m running PHP 8.1, Woocommerce 8.7.0 and WordPress 6.5.2, perhaps the plugin hasn’t been updated to the latest versions?