Hello
Can you please go to Settings > Accounts > Access Work or School (Note, it is the brief case icon, not the envelope icon). Do you see an organization email listed? If you do, click on it and then disconnect it. Restart the computer.
If you are still being prompted for pin change, First, can you please go to Settings > Accounts > Access Work or School, and make sure there's no work/school email address listed there, or no mentioning of Azure AD. If there is, please click on it and then click on disconnect. Then restart the computer and see if it is resolved.
If not, or if nothing is listed there, please type cmd in the search on the taskbar and make sure you select "Run As Administrator" to launch Command Prompt.
Run the following commands, one at a time. Not all of them will go through completely or value can be found, and that's ok. Once finished, restart the computer again and see if it works.
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