You will need to remove all of the options from the Alert Suppression Tab. Under the Alert Suppression it is currently configured that if any of the Interfaces reports as down or any Interfaces is Unmanged, the Alert becomes null and void and none of the other Interfaces are Triggered.
Once you remove the Suppression, the Alert should work as expected.
Background about the Alert Suppression Tab. This was created back in NPM 8.1 as the precursor for Dependencies, so that if a device was down that it would suppress the Alert for the other devices associated to the down device.