Hey guys. Whenever I try to spawn spiders, zombies, pigs, sheep, and cows, the animals don't spawn but it sounds like they are. When I use the /spawnmob command, the same thing happens with the same mobs. The rest are fine. I can't get these mobs to spawn with monster spawners either. Horses will spawn, but whenever the chunk unloads, they disappear. I've turned on mob spawning in the server.properties file, but what confuses me is that the animals which aren't spawning are random ones; some are passive and some are not. I've been trying to fix this for a while but I honestly have no clue what I should be doing anymore. Thanks for any help in advance!