Windows 10 lock screen wallpaper problem?

You can set the background image to show lock screen on login screen. Unfortunately this does not work.
As soon as I enter the password, the picture disappears and the background turns black.
I noticed (because I duplicate my screen) that the background is there on the TV, just not on the laptop?! As soon as I select PC screen only, it works.

What could be the reason that it is not working properly?

What I do not understand, everything worked before the Windows Update. Yesterday I opened the 20H2, now it looks like this. And why does the TV show it to me correctly but the laptop doesn't, even though the laptop mirrors everything?!

But where is the problem? It's made in such a way that it gets out of focus

Yes, but it only works on the TV and not on the notebook itself. Before, it worked on both at the same time.

That's why I took the picture