hermanv thanks you for your comment.
My mlmmjadmin.service works. So it's probably something else
mlmmjadmin.service - RESTful API server used to manage mlmmj mailing list manager
Loaded: loaded (/lib/systemd/system/mlmmjadmin.service; enabled; vendor preset: enabled)
Active: active (running) since Thu 2020-08-06 00:49:59 CEST; 2 days ago
Main PID: 1302 (uwsgi)
Tasks: 6 (limit: 4441)
CGroup: /system.slice/mlmmjadmin.service
├─1302 /usr/bin/uwsgi --ini /opt/mlmmjadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/mlmmjadmin/mlmmjadmin.pid
├─1486 /usr/bin/uwsgi --ini /opt/mlmmjadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/mlmmjadmin/mlmmjadmin.pid
├─1487 /usr/bin/uwsgi --ini /opt/mlmmjadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/mlmmjadmin/mlmmjadmin.pid
├─1488 /usr/bin/uwsgi --ini /opt/mlmmjadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/mlmmjadmin/mlmmjadmin.pid
├─1489 /usr/bin/uwsgi --ini /opt/mlmmjadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/mlmmjadmin/mlmmjadmin.pid
└─1490 /usr/bin/uwsgi --ini /opt/mlmmjadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/mlmmjadmin/mlmmjadmin.pid