events

it is set so that NPCs do not cause damage to buildings but buildings are still destroyed by tanks and helicopters

Its a bit unclear to me what you are suggesting here, could you elaborate some more?

I have set that NPC can not do damage but for example the tank of the convoy can destroy the base

Currently NPCs actually refer to "fake players" that are created by plugins like BotRespawn. I know the name is a bit confusing, but currently this plugin does not provide protection against things like Animals, Scientists, or Tanks/Helis. So this is intentional for the time being.

Changed Status from Pending to Not a Bug