Italian tax code is not valid

Hello. I’m trying to update my Arduino Store profile, as I’d want to place an order. Yet, it says “Tax code is not valid” although I’ve checked the form and all the fields are correct.
Is it a problem of the website or only mine? :~

EDIT: Solved, it has just been corrected.

I still have the same problem! What do you suggest?

For that kind of issues, send a mail including the actual tax code you have to input to
webmaster@arduino.cc
or
store@arduino.cc