"Mobile Devices setting" is controlled by an organization

1

Open the Settings App.

Go to Accounts.

Select Access Work or School, is there is a work or school Email listed there?

2

If there is no work or school account listed in there.

Click your Start Button, then just type cmd

On the resulting list, right click Command Prompt and select 'run as Administrator'

Paste each of these commands into Command one at a time and press Enter, wait for each command to complete, before running the next command, if you receive an error on any command, ignore that and continue to the next command.

reg delete "HKLM\Software\Microsoft\Windows\CurrentVersion\Policies" /f

reg delete "HKLM\Software\Microsoft\WindowsSelfHost" /f

reg delete "HKLM\Software\Policies" /f

reg delete "HKLM\Software\WOW6432Node\Microsoft\Policies" /f

reg delete "HKLM\Software\WOW6432Node\Microsoft\Windows\CurrentVersion\Policies" /f

reg delete "HKLM\SOFTWARE\Policies\Microsoft\Windows Defender" /v DisableAntiSpyware

reg delete "HKCU\Software\Microsoft\Windows\CurrentVersion\Policies" /f

reg delete "HKCU\Software\Microsoft\WindowsSelfHost" /f

reg delete "HKCU\Software\Policies" /f

reg delete "HKLM\Software\Microsoft\Policies" /f

Then, close Command Prompt and restart (not shut down) your PC.