Change in Minecraft Difficulty Settings Affects Monster Spawning Differently for Host and Guests

After switching the difficulty level in my Minecraft game from normal to hard, I noticed a significant decrease in monster spawns for my character while other players in my world continued to experience normal spawning rates. Strangely, when I'm near these players, monsters stop spawning, but they reappear for the other players when I move away. Even after reverting to the previous difficulty level, the problem persists.