You should be able to remove the PIN in Settings > Accounts > Sign in Options:
https://www.howtoedge.com/enable-or-disable-hel...
If not Here's here how to reset the PIN in Windows 10 when it will not work right from Settings > Accounts > Sign In Options:
Open Windows File Explorer using the file folder icon on your task bar.
Tick the box in File Explorer View tab to Show Hidden Files.
Browse to C:\Windows\ServiceProfiles\LocalService\AppData\Local\Microsoft\Ngc
Delete or rename to Ngc.old this folder to reset the PIN.
**You may need to first take ownership of the folder: https://www.tenforums.com/tutorials/3841-add-ta...
Once you delete or rename the folder it will recreate it so you can add a PIN normally in Windows Settings > Accounts > Sign-In Options. You may need to restart the PC first.
For any unexpected problems see tutorials covering all possible problems here:
https://www.askvg.com/fix-unable-to-add-and-use...
https://www.lifewire.com/remove-pin-from-window...
To turn off nag messages to use a PIN see here:
https://superuser.com/questions/1322150/how-do-...
https://answers.microsoft.com/en-us/windows/for...
Based on the results you post back I may have other suggestions if necessary.
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