Vray 5 perpetual upgrade to 6 perpetual error

[dejan_parovec]

Hi, I'm trying to upgrade my vray 5 perpetual license to vray 6 perpetual, but every time I try, I get this error: "Oops... Something went wrong. Invoices cannot be generated in a closed Accounting Period. Please enter another invoice date."

I have no idea what this means or how to fix it. There is nothing to enter on that page. I have sent a ticket 7 days ago but with no reply. I understand there are a lot of questions but this is a really long time now...

Thanks!