Parallels 12 For Mac OS Sierra 10.12.6 - "Try Free" Link Doesn't Work

Hi folks, I'm hoping to get my old Mac Pro tower up and running with Parallels 12. The software downloaded and installed just fine, but when I click on the "Try Free for 14 Days" button, it points to a dead link (screenshot attached). Clicking the "Buy Now" button takes me to the main Parallels 19 page, not Parallels 12.
I'd love to see if this thing actually works before purchasing it. Is there a workaround? Or if purchasing it is the only option, has anyone discovered a way to do that?

 

Thanks for the replies, all! True, Parallels 12 is outdated, but as I mentioned, I can't run newer versions on this old Mac running Sierra. I've since learned that P12 is no longer available as a Free Trial OR a Purchase. Which begs the question: why tease us with a download option? I tried to source a private party with an Activation Code but haven't had any luck, and I'd rather avoid using a crack. So I'll cut my losses and look at BootCamp or another option for this old Mac.

 

Thanks, JohnW110... you're right, P12 being older software, neither the Free Trial nor Purchase links are active. Which begs the question: why allow users to download software that's completely useless? Sadly, this Mac Pro's OS can't be upgraded any farther than it is, so the whole Parallels exercise was a time-consuming dead end. Instead, I ran Apple's BootCamp, so I can now run Windows 8. It's less elegant, as you have to reboot the Mac to get to Windows... but unlike Parallels 12, at least it was an option.