I have the same problem. I have a valid VAT ID registered in the UK but the system is not accepting even if I enter the exact VAT format mentioned in the VIES website.
Please, can you help me with this?
Hi Daniela Elizabeth,
I'm sorry to hear you are running into issues with using your VAT number on Upwork. Could you please check if the VIES website is able to validate your VAT number?
If so, please add your VAT number in the same exact format that VIES is able to validate it.