If they’re crafting/bench thralls there are multiple bugs with the Living Settlements including the death of these thralls.
Here we pushed to get Living Settlements disabled on Officials, requesting for the feature to be ironed out first before enabling again.
Funcom announced it would be switched off (pending possibly multiple server restarts) for April 30th, however there was some kind of issue that prevented the servers from disabling Living Settlements.
Assuming that it works this time, Living Settlements should be disabled come next server restart.