Mac activation block

I have updated my Mac

mini 2018 to Sonoma.

It does not start anymore.

The only available solution I found is internet recovery (option-cmd-R) but at the end of the rotating globe process I get a startup error message code - 1008.

i assume my mini has an activation block which prevents the Mac from starting up. Is there something I can do except remove this Mac from localisation in my iCloud account. Will it be sufficent to allow the Mac recovery and startup.

Thanks in advance for helping.