Mob Spawn not working ( nukkit petterM1 )

[ShFIso]

i runned nukkit petter m1 edition and spawn mob and . . . is enabled and radius is 64 but mob spawn doesnt work

 

[PetteriM1]

Check that
- /gamerule domobspawning is true
- spawn-mobs=on/spawn-animals=on in server.properties
- worlds-entity-spawning-disabled does not have the world listed in server.properties
- ticks-per-entity-spawns > 0 but not too high and ticks-per-entity-despawns not too low in server.properties
- difficulty > 0 in server.properties for monsters to spawn
- no plugin is disabling it