I'm using softwareupdate command line tool to update macOS version. I run this command to perform an update but it only downloads the patch and does not install it.
sudo softwareupdate --install '%patch_name%'
Ex: sudo softwareupdate --install 'macOS Big Sur 11.6-20G165'
On macOS 10.15 or older I can update with command but on macOS Big Sur it cannot update. I checked on multiple virtual machines and see that the issue happens from macOS Big Sur and later. If I want to update I must use Software Update UI on Preferences. Does anyone know the root cause and help me on this issue?