The title says it all; I flashed a new Samsung EVO 32G TF with the 20.04 release from here https://ubuntu.com/download/raspberry-pi using the 32 bit one. It seems to boot, the stats lights seem like they're doing the right thing, I even have a Bluetooth card set up AMA0 with a getty to enable a console login. The system will ask for credentials, but ubuntu/ubuntu doesn't work. Some sites say leave username and password blank, others suggest root for either or both, tried all of that.

I can just reflash the card I guess, but it does look kike everything worked, I even get a ssh session on the LAN, where I can't login.'

Sorry, but if a basic question but run out if ideas.