Turning off Device Enrollment Notifications on MacBook Pro

I have purchased a MacBook Pro a year ago and after upgrading to Sierra started to receive notifications from a company that owned a laptop before. I have tried contacting Apple Service and the actual company, no luck so far. I have learned that I need to find two files: /System/Library/LaunchAgents/com.apple.ManagedClientAgent.enrollagent.plist /System/Library/LaunchDaemons/com.apple.ManagedClient.enroll.plist But I can't move them (and even create folders where they can be moved): /Library/LaunchAgentsDisabled and /Library/LaunchDaemonsDisabled Can anyone please help how I can turn off device enrollment notifications?