Grafana sends a blank email after each notification

I have a problem with the configuration of email notifications that I can’t fix. I created a notification rule as shown in the screenshots below:

Everything works fine, grafana sends an email with the log:

However, this message is followed by another blank email

I’ve tried different configurations, silencing, upgraded Grafana to version 10.4.0, created the rule anew but none of these things help.
Maybe one of you has encountered such a problem and can point out to me where I am making a mistake.