Strange bug - no spawn after couple hours of botting

Hi there, so today I saw really wierd bug with spawn. We were testing the server, and left a char to bot at Niya Shamans. In first 2-3 hours everything was okay, but after about 4 hours mobs just gone, empty. There were no spaw at all where the char was left, and not a single mob spawned from 3 AM untill I restarted gameserver. I use only one mashine, but most of regions are turned off, only China(without Tomb), Oasis Kingdom, West China, SIEGE_DUNGEON, Thief Village, and all three forts are left online. Also I'm using Chernobyl's evangelion gameserver addon v1.0.5
Can this tool be the problem? :ehh: Big thanks.