Make sure you are using latest version of the live editor.
Reset Live Editor settings to default. (run LiveEditorClearRegistry.reg that you can find in the folder with live editor and delete FIFA 23 Live Editor folder from C:)
Go Online on EA App (this is required for first run)
Change injection delay
Run game without mods and without advanced launch options (like -dataPath FIFAModData)
Move the live editor to the folder with the game
Make sure the windows user that you are currently logged in on has full admin rights.
Change game installation directory to somewhere that doesn't require admin rights
Go to your game installation dir -> FIFA23.exe -> Properties -> Compatibility and uncheck "Run as Administrator"
Make sure your antivirus isn't a problem
Try to start live editor launcher and then instead of pressing "run game" button start the game from EA App
I open the live editor, the game appears on the screen, but then the live editor closes itself.