Fantastic thank you when will the update be available?
DietPi 7.2 will be launched on 2021-05-29.
check our online docs 
https://dietpi.com/docs/releases/
Latest dietpi still has same issue. Any configuration made on webmin stops webmin and it doesn’t restart.
I guess the fix is available on new installations only as the service file would need to be changed. Can you share yours
cat /etc/systemd/system/webmin.service
[Unit]
Description=Webmin (DietPi)
[Service]
Type=forking
ExecStart=/etc/webmin/start
ExecStop=/etc/webmin/stop
[Install]
WantedBy=multi-user.target
yes it is still the old one. I guess you would need to change it manually
[Unit]
Description=Webmin (DietPi)
Documentation=https://doxfer.webmin.com/Webmin/Main_Page
[Service]
Type=forking
GuessMainPID=no
SyslogIdentifier=Webmin
ExecStart=/etc/webmin/start
ExecStop=/etc/webmin/stop
ExecReload=/etc/webmin/reload
[Install]
WantedBy=multi-user.target
or perform a reinstallation
dietpi-software reinstall 115
Reinstall worked Great! Cheers