Yeah, I have checked "Permit" and not "Prevent".
I think I have solved this now.
The mac address on sticker on the cam and the mac address reported in the setup wizard is the same.
But.......I clicked around in the camera web interface and under Status I could see another mac where one character differs from the one on the sticker.
I added that new mac to my mac filter list....and guess what? It works.
Could you please please explain why the sticker and the setup wizard reports wrong mac?