How to restore fingerprint password after installing Golden Gate 27.2 on iMac?

If you are using an iMac with a wireless Magic Keyboard with Touch ID, the update can temporarily break the secure connection between the Mac and the keyboard, causing your Touch ID settings to appear completely greyed out or unselectable. 

Follow these steps to re-link your hardware and restore your fingerprints:

Step 1: Re-link your Magic Keyboard via Cable

If the usage options are greyed out, your iMac needs to establish a direct, wired trust connection with the keyboard's Touch ID sensor again. 

• Connect your Magic Keyboard directly to your iMac using its USB-C to Lightning (or USB-C to USB-C) charging cable.
• Turn the keyboard's power switch Off, wait 5 seconds, and turn it On again.
• Leave it plugged in for at least 10–20 seconds to allow the Mac to re-authenticate the hardware.

Step 2: Clear and Reset the Settings

• Click the Apple menu  > System Settings.
• Scroll down and click on Touch ID & Password.
• If you see any ghost fragments of your old fingerprints left over, hover over them and click the (X) to completely delete them.
• Once cleared, Shut Down your iMac entirely (do not just restart).
• Turn it back on and log in using your standard login password. 

Step 3: Re-add Your Fingerprints

• Go back to System Settings > Touch ID & Password.
• The options should no longer be greyed out. Click Add Fingerprint.
• Enter your account password when prompted.
• Follow the on-screen prompts to repeatedly lift and rest your finger on the keyboard's Touch ID sensor until it registers completely.
• Toggle the switches back On for "Use Touch ID to unlock your Mac" and any other desired preferences

More info from Apple: Touch ID & Password settings on Mac - Apple Support

Do you not see System Settings > Touch ID & Password?

If you can navigate to that, remove the existing finger id's

and create new ones. If you hover the mouse over each finger print

you will see a tiny "X". Clicking that on each finger print will remove them.