csrutil disable
Restart computer
In the terminal, type
sudo open /Applications/TextEdit.app /System/Library/LaunchDaemons/com.apple.ManagedClient.enroll.plist
change
<key>com.apple.ManagedClient.enroll</key>
<true/>
to
<key>com.apple.ManagedClient.enroll</key>
<false/>
So that the changes take effect
Possibilities - The profile could be downloaded and installed during setup, the hostname/IPs are cached (mDNS/DNS), you have some other third part software doing some kind of networking manipulation, you have not declined the profile in the settings app, you have not requested the "profiles" app to clear/delete past profiles.