Cubase 10 zipfile issue

Several months ago I got an offer from Stienberg to download CuBase10. At that time I was not running Win10, which was required, but I downloaded it anyway. . I just migrated to Win10 and tried to load the program. I got an error message saying the installer zip file was corrupt.
What do I do now?

Use the Steinberg Download Assistant to download it.

OK, I tried to load that way which seemed to work/ But it won’t open because of no active registration. When I tried to register Cubase 10 is not listed. Interestingly neither is LE8 which is on the older machine.
So now I mostlikely have a valid installation, but no access code.
I’m sure this is a fairly small problem, but it has me baffled.

Thanks in advance

Please read Software/license activation & reactivation – Steinberg Support