Partial login loop after lock screen in 20.04

I’m having an issue since I updated to 20.04 that I’ve not found answer for going through the login loop questions already published.

The loop I get into happens after I try to log back in after locking the screen. Everything looks normal and after entering the password the desktop or whatever window was open is shown and then Ubuntu goes back to the login screen with a different theme that stays after entering the password again. The new theme makes it very hard to see whatever is on the top bar, changing volume with the mouse, or when I search for apps to launch (all icons are black).

This behavior happens always, but sometimes I need three logins instead of two. If I go to a terminal window with the function keys and then back to the graphic interface things look normal but then I have to log in again with the same issues.

When coming back from Suspend, I directly see the wrong theme login screen.

Thanks for your help.