SU2021 deleted SU 2020. SU email with Serial and Activation Code does not work on SU2020

[planetoonsguy]

I had a licensed version of SU2020 Pro and was using it for over a year without problems. I downloaded and installed the trial version of SU2021 Pro and decided I did not want to pay that much for it. I uninstalled SU2021 Pro and could not find SU2020 Pro anymore. It was gone from my computer. No other upgrade of SU 2017 Pro, 2018 Pro, or 2020 Pro deleted the previous versions.
Downloaded and reinstalled SU2020. License info from email with Serial Number and Authenticate Code did not work. Got notice on website that my Serial has changed from “V” to “WV.” Tried getting an Authentication Code from Authentication Manager. None of the codes worked using either the “V” serial number or “AV” serial number.
I would like to get back my working version of SU2020 Pro which I paid for.

[colin]

I will lock this topic, as the problem was solved in this other topic:

Subscription won't activate

You installed and activated your 2021 license late November, just under a year ago. Doing that will have made your 2020 license be deactivated. Any existing 2020 installs would still work, but you wouldn’t be able to activate 2020 on a new machine. Your 2021 license is still active, you can install 2021 and your 2021 license, and SketchUp will work. You do not need to pay for a subscription. Unless there is a reason for using 2020, you could reinstall 2021, check to see if the license is still …