Slitherine

I am playing as Rome. Latium has started out with fourteen population. It always has surplus food, and several turns of food in storage.

Yet the population never rises above fourteen, even when slaves are sent there after a battle, and after twenty three turns, its population has dwindled to twelve, despite plentiful food. No explanation or notification of this drop is ever given in the notifications or elsewhere, and I am at a loss to understand why this is happening or what to do about it. If there is disease or a disaster, no notice of it is given.

If anyone can explain ti, i would be very interested to know what is going on.