UVI is a French company based in Paris. If you are currently registered as a business company based in the European Union but outside of France, you are probably exempt from Value Added Tax (VAT).
You can update your UVI account by entering your VAT number on the Addresses page. By doing so, you will be tax exempted when shopping on the UVI Store.
Please make sure that you are actually exempted from VAT for purchases in the European Union before you fill in your VAT, otherwise please ignore the optional field for the VAT Number on the Addresses page.