Emails from senders as the owners of a contact don't arrive but still get marked as read

Your software
My Mautic version is: 4.4.3
My PHP version is: 7.4.32
My Database type and version is: pdo_mysql and 5.7.39-42-log

Your problem
Hi everyone, my installation is only just a few days old and I’m still trying to get around.

According to How do you configure Mautic for multiple emails to the same domain, I can config the owner of a contact to be the sender, for example for a one-time email.

It strange that Mautic says the emails was sent and read even though nothing arrived in my inbox

These errors are showing in the log:
The log in config/System Info/Log is empty

Steps I have tried to fix the problem:
There’s a separate account to “simulate” a salesperson
I tried to manually run the cmd
php path/to/console mautic:emails:send
which finishes without output

as well as
php path/to/console mautic:messages:send (although this one is for marketing messages afaik)
the output is
Processing message queue
Messages sent: 0

cronjobs all work fine
2,17,32,47 * * * *
php path/to/console/console mautic:messages:send
8,23,38,53 * * * *
php path/to/console mautic:emails:send