CUbase Pro12 can't activate

I purchased Cubase Pro 12(update from 10.5) .But I can’t activate it.
The following is my activation process.
I open Steinberg Download Assistant and enter the DAC to upgrade my elicense.


Finally, it shows No License To Upgrade Selectable.
And when I opened the Steinberg Activation Manager.It shows the application error and the application cannot start normally(0xc000007b)
I don’t know which step I did in a wrong way.I need your help.


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