How do I stop the trial and revert back to my previous version?

I have had Parallels running on my Macbook Pro for about 2 years with Parallels for Mac. I have upgraded when new versions were available, but I am not sure what version I was running when I mistakenly accepted the trial version of Parallels 12 Pro. First, how do I determine which version I was previously running? I assume v11. Second, how do I stop the trial?

 

Hello @JimC7
Here is how can find the version of Parallels Desktop installed on your Mac. To find the version of Parallels Desktop you were running previously, log in to your Parallels account & find the license key as outlined in this article. However, we could see that you have Parallels Desktop 9 for Mac registered under your email address. You can uninstall Parallels Desktop 12 and reinstall Parallels Desktop 9 for Mac but please check Mac OS X compatibility before reinstalling Parallels Desktop 9.