No emails are sent when someone is taking a leave

Hi,
Whenever someone take a leave the managers are not receiving any emails or notifications.
I use WP Mail SMTP plugin and rest of the forms are working ok. Test from WP Mail SMTP works ok. Even when sending test from WP ERP/Emails/Email Connect is successfully send and received successfully.

In another topic of yours I saw suggestions for Email Log plugin. All emails from the website are there except the WP ERP including the test email that Is successfully send and received successfully.

I have tried disabling all addons and clean theme but the problem persists.
I have no idea what to debug next. Any help is appreciated.

Thanks,
Gorast