Users don't get registered when trying to register blog at signup

I don't know what happened. This was working ok a few days ago. Tried switching themes and removing plugins, still an issue. I've read through the forums for hours, tried lots of things, still not showing up under users or getting their activation emails when signing up a blog at registration. Checked settings, "Both sites and user accounts can be registered" is on. Pulling my hair out trying to find this problem. I'm going bald.