Good afternoon.
This happens because you had such letters from 2023-05-04 and 2023-05-016 in the queue for sending
https://i.imgur.com/ykOumEf.pngApparently you have not correctly configured integration with mail.
Box tries to send emails every minute.
When sending, your mail server gives an error, so the letters are not removed from the queue for sending, but the letters are sent (so you receive them every minute).
Checking the SMTP TLS checkbox (in the integration settings) solves the problem with the integration, and the messages were marked as sent.
https://i.imgur.com/vKVgw9h.png