frustrated upgrade - help needed

We own a mac and use the Window parallel version at home. We purchased Window 10, but today it actually stopped working today with a blue screen showing the some portion was no longer working. Here are the exact steps that followed.

1.) I purchased the upgrade to Window 11.
2.) I downloaded the new application and put in my key code.
3.) It told me that I was in the old application, so I closed it and finished what I thought was the new download. What actually came up though was the old version again with the blue screen of death.
4.) I dragged the Windows 10 to the trash and tried again.
5.) This time it tells me that a device is not available.
6.) I contacted support and they tell me key is already being used. That's it. No other help.
7.) I still cannot get in. I need help.

Please help. Thanks Tim & Cindi