Touch ID not available suddenly
My iMac (2021 M1) was set up for Touch ID, but it suddenly became unavailable (not given as an option) for lock screen and passwords etc. In systems preference in Touch ID the text is all greyed out. On googled advice I deleted the fingerprint registered hoping I could add another but its still all greyed out and won't let me add another fingerprint? I am on the latest version of Monterey. I have rebooted and done the obvious things. Please can you help??
iMac (M1, 2021)