Hello
Thank you for posting in Q&A forum.
What account do you sign in the machine now?
You can try to turn off the settings below in your screenshot and then check if it helps.
You can change another account on this machine and check if you can set and change PIN.
Is your machine in one domain or workgroup before and now? If your machine is in one domain, maybe your domain administrator set the setting via domain GPO setting, you can try to check with your domain administrator.
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best Regards,
Daisy Zhou
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