iMac unlock not working with Apple Watch?

Question

macOS

I bought myself an iMac, set it up as described in the tutorials. Checkbox "use aple Watch to unlock is worth it", wifi, bluetooth are enabled. Are situated in. one apple id. Two-factor authentication is enabled, there is a password on the clock (when I try to unlock it, the password on the clock is removed naturally). I also know that at the first start it always asks for a password, when sleeping or blocking it does not even try to work through the clock, it immediately asks for a password.
But if on the iMac in the same Protection and Security tab you click on the lock from the bottom, then there is a request for the clock and you can click on them to skip entering the password.
What am I doing wrong and how do I unlock my computer for hours after sleeping or locking the screen?