That was the problem I think. You set up your device for MDM (mobile device management) what companies usually use to roll out policies and restrictions to the employees business phones. Now the devicce expeccts a config file or something like that from a MDM server, which you obviously don’t have and want as private person.
At this point you’re no longer the complete “master” over your device.
I have no idea if this can be fixed by resetting the device. If possible, I would factory reset the device and start the setup again. And before you do this step that lead you to this point share a screenshot and the community hay help you with the instruction.
The buzzwords were “organisation” and “IT-manager”.