Unable to pay annual personal plus template

Hi,
for a few days I have been trying to buy your template, Zakra, annual, professional plus. Unfortunately, every time I try to buy (with credit card and also with Paypal) with my VAT (my company is based in Italy) I read an error message:

“An error occurred while processing the card. Please try again in a few minutes. vat_id must be a valid VAT ID”.

I check it and my VAT is correct, and also the credit card details and Paypal account. How can I proceed with the purchase? Thanks.

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