Change keyboard type button missing in System Preferences

Hi everyone. I had some trouble with my external USB keyboard on my Mac M1 2021, I changed the keyboard type a few months ago so I could use properly the key next to the Z key which for me the symbol is <> . Everything went fine for a while. I use that key a lot because I'm a front-end developer and I write code every day. Now I changed back by mistake to ISO and the button has disappeared. I spent 3 hours today to fix it. No fix.

For example this:

1) Delete the file: /Library/Preferences/com.apple.keyboardtype.plist

2) Restart

Also Repaired Disk Permissions on Mac, I removed /Library/Preferences/com.apple.keyboardtype.plist

Another possibility may be to open Terminal and type:

sudo open /System/Library/CoreServices/KeyboardSetupAssistant.app/Contents/MacOS/KeyboardSetupAssistant

Now I'm here. Nothing worked. Also updated to MacOS Big Sur 11.4

thanks..