Try these steps in order:
- If PIN (Windows Hello) is available but Change PIN is unavailable, go to Settings > Accounts > Sign-in options > PIN (Windows Hello) and select I forgot my PIN. Follow the prompts to verify the account and create a new PIN.
- If the PIN is not working correctly, sign out of Windows and sign back in, then try the PIN action again.
- If the PIN still shows as unavailable, sign in with the account password instead of the PIN, then go back to Settings > Accounts > Sign-in options and remove and set up the PIN again.
- If the device has fingerprint sign-in configured, sign in with PIN or password, then re-register the fingerprint from Settings > Accounts > Sign-in options > Fingerprint recognition (Windows Hello) > Add a finger or remove and add it again.
- If this is a domain-joined Windows device, the PIN option can be unavailable because of policy settings. On Windows 10 version 1607 and later, a convenience PIN cannot be created if both Use Convenience PIN and Use Windows Hello for Business are enabled unless the device is joined to Microsoft Entra ID in a supported way. In that case, the relevant policy configuration must be corrected.
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