https://politicsandwar.com/nation/id=185945 https://politicsandwar.com/nation/id=186793
The above two have the same Unique ID: https://politicsandwar.com/nation/unique/id=186793
And they two both have declared war on me before in the same period of time (though both nations lost). This already broke the rule, and further, I suspect they are the same users.
There are also two more nations of the same unique ID, however those two have not fought me.