Italy address service - error while changing province

Hi experts,

I am trying to change the permanent address for an Italy employee thru ESS, but I am getting an error below:

The combination between city and state is not valid.

Scenario 1 = Let say the original province is Milan, and i am just changing the existing city to another city in Milan, it allows me to save.

Scenario 2 = If I changed Milan to another province "Brescia" and also update the city to another city in Brescia. It will throw me the error.

I have no problem changing a province from Backend.

Any idea??

Thanks

Regards,

J-Lim