Modeled Mobs Take Fast Suffocation Damage When Damage Is Edited

For some reason when a modeled mob takes damage and the damage is manipulated via a plugin, the modeled mob will take suffocation so much faster than normal. The following code is what I've tested. The issue seems to only occur on mobs that have a model attached to them.

@EventHandler(ignoreCancelled = true)
public void onEntityDamage(EntityDamageEvent event) {
    switch (event.getCause()){
        case SUFFOCATION -> {
            Bukkit.broadcastMessage(event.getDamage() + "");
            event.setDamage(event.getDamage()*.7);
        }
    }
}

When I comment out the "event.setDamage(event.getDamage()*.7);" part, the issue is no longer present. It's weird...