Taxation area problem

-- HikaShop version -- : 2.6.3
-- Joomla version -- : 3.4.8
-- PHP version -- : 5.5.32
-- Browser(s) name and version -- : chrome

Hi,
i have another problem, now with taxation area, see the image in attachment.
I want to configure the system to allow buying only from Italy.
Then, in the areas page, i turned off all the country and i published only Italy.
I turned off also all the state except those related to Italy.
I have only one taxation area: Europe.
I don't have shipping area.
When i try to select the taxation area in the main configuration, i receive the error in the image.

Then, if i try to make a ch eckout with a test user, the system don't show the state combo box like in the second image.

Where am I wrong?

thank you!

Hi Nicolas, excuse if i anwser late, now i try and then i let you know.

thank you.

Marco.