One of my provinces has Death +3 scale!!

[FNC]

It happened for no apparent reason! My dominion there is 4.

What happened and what can I do to change it??

[Norfleet]

There's probably an undiscovered magic site that causes death scale to rise there. If you took a strong growth scale and strong dominion, your scales should probably reassert themselves in time. If you didn't, that province is just permanently going to suffer from high death scale. You can just ignore it, or pillage it and kill everyone first