Installation of SDL Trados Studio 2021 and applying a discount

Hello, 

I have seen that as a Proz.com member I can get a 30% discount if I purchase SDL Trados Studio 2021 by  Oct. 31, 2021. I currently use a trial license and would like to do that. How can I apply that discount? do I have to buy it while I'm logged in to proz.com and download it again or how does it work?

Best regards,

Rafaela Bielecki-Weyenberg