Monsters in Peaceful Realm

Went into settings in Peaceful Realm. Toggled to Normal diffculty. Battled monsters for a couple hours. Toggled back to Peaceful. Game is still in Normal difficulty. Monsters persist and still spawn. Food still has to be eaten.

Have done this for months with no issue. Toggling monsters on for a bit then back off. Can't toggle them off now. Ruins the paid realm .