I am having the same problem as this post: Windows Hello PIN/Fingerprint "This option is currently unavailable"
I changed the same three polices in the solution to be "Not Configured"
under Computer Configuration\Administrative Templates\Windows Components\Windows Hello for Business\ must be in the state "Not configured".
I had mine set to Enabled. I changed to Not Configured. I have "Turn on convenience PIN sign-in" enabled - I checked my registry and it is showing on.
Still getting unavailable. Is there anything that must be done to "fix" or overwrite the settings that were made when these were set to enable.
If not, I am wondering if I have an InTune policy that is impacting it.