Trial expired: how can I resume using my existing licensed version?

I have parallels 10 and did the trial upgrade to 12. I didn't see any improvement for my use cases so I'd like to resume using 10 again... How can I switch back?

 

Hi, you can download the Parallels Desktop 10 from this link http://www.parallels.com/products/desktop/download/
and then install it and activate with your license key

 

Please let us know if you get any difficulties with installation or activation.