I was able to login with my Apple Watch on Macbook Pro. With Macmini I can only log in from sleep mode.

Hello us_heidi,

It looks like you've had the opportunity to review the details in the related article above: Unlock your Mac with your Apple Watch - Apple Support

Since that still persists, you'll want to reach out to Apple Support: Apple Support They'll be in the best position to look into this further.

Take care.

I have the same problem on my MacMini (2018). Interestingly, I get requests to approve passwords on the Apple Watch from this MacMini.

Francis

Yes, I can confirm the same as @us_Heidi: I can log in from sleep mode only. I have to login in with a password from the lock screen.