[FAILED] DietPi-Services | Root privileges required. Please run the command with “sudo” or “G_SUDO”.
The reason that I use DietPi so much is that I am not massively familiar with Linux and so don’t know whether I am even going down the wrong rabbit-hole!
If you added a service with dietpi-services then it got added to /etc/systemd/system which will always be controlled by user root, I think you will always need sudo to run it.
However, you can run it as a regular user by adding usr and group to the service file.
There is a discussion here https://askubuntu.com/questions/1371102/running-systemd-service-as-user-rather-than-root
I have not tested this, please report back if it works as you want it.
The other option is to create a user service and run that, see above link.