Same issue here. All info I have entered is correct, I got valid VAT ID. I even tried adding letter preffix before numbers versus entering without letters, just numbers. All I get is not approved.
Please take a look at my issue, since I have already tried number of times.
As all the rest, I have a valid EU VAT ID that can be verified on VIES. Upwork will just not validate it. It is the right format, right company name, everything is correct. Done this 3 times now and still receive a message tha I should resubmit.
In addition the support ticket link you provide is dead.
Thank you in advance.