No mob random Spawning at all

At night no hostile mobs seem to spawn. After further investigation, passive mobs also fail to spawn. No mobs are spawning in the nether either. 

However, if no players have recently visited the nether then loading the nether will temporarily fix this issue.  After a few minutes in the Nether the hostile mobs (enderman,  Ghasts, and Piglins) will despawn leaving only the zoglins. 

Villages still spawn Villagers, Iron Golems, and cats. 

Spawners still spawn zombies and cave spiders. (Others likely still work but I have not found any others) 

 

UPDATE: This only happens when 3 or more players are on the realm.