Installation Failure
When a user uses the menu app to allow Kandji to update or upgrade macOS, and that MDM-initiated update or upgrade cannot complete successfully, the menu app guides the user to manually complete the update or upgrade via System Settings or System Preferences. If the user ignores that initial prompt, the Kandji menu app will continue encouraging the user to complete the task, with increasing frequency over time. This helps ensure that all users update to the appropriate macOS version as soon as possible.
In some cases Update doesn't work through system settings. In that case, updating through Powershell will help : Use command sudo Kandji run -F to run all updates
It will ask for system password, once done , restart the computer and it will complete all pending updates.