You configure your service (ie sshd) through UMC or ucr-Variables but the configured changes are not taken into account by the service. Even a reboot does not help.
You might have modified templates in place which might have fixed the settings you are trying to change.
Identify the template which has been edited:
WARNING: The following UCR files are modified locally.
Updated versions will be named FILENAME.dpkg-*.
The files should be checked for differences.
Edit the found template file and revert your changes.