new version update bought, but lost activation key to the original version

Hello!
Seems that 5 years have passed and a simple update didn't work anymore to continue working with parallels desktop on MacBook.
I've bought the newest parallels desktop version update, but seems that the original activation key has been lost.
Is there a way to get the previous activation key, should be the same email address.
or
if that's not possible, then can the price of the updated version (which has already been bought) be deducted from a full versions price?
Best regards

Janis

 

An upgrade to Parallels Desktop 12 for Mac is possible only from Parallels Desktop 11 and Parallels Desktop 10.
As you've already purchased an upgrade version, we've processed the refund for your order. Refunds usually take 5-7 business days to appear in your account.
Please purchase a full version of Parallels Desktop for a successful activation.

 

Hello!

I'll do so, thank You for the refund of the upgrade purchase.
All the best,
Janis

 

Sounds great! Here is the user guide for Parallels Desktop 12 for Mac.