Activation Manager and Cubase Pro 12 License issue

I switched computers a couple of months ago, and I was able to successfully reinstall and validate my Cubase Pro 12 License. It worked fine until tonight; I was noodling around with Cubase templates and for some reason, after I had exited and tried to restart the program it said “no valid license found.” I’ve been trying to troubleshoot the issue, even going so far as to reinstall the Cubase program itself several times, but it still says the same thing. When I try opening the Activation Manager, it stays on the loading screen but… doesn’t load.
Additionally, I went to check my license status on the Steinberg website and it says it’s perfectly valid there, and still appears in the Download Assistant. Really frustrated here, any help?

First step. Reboot system. Cold reboot, as in turn off, wait, turn on. I know this is obvious but you didn’t mention if you had done it.

Reinstall SAM latest version.

Also check your Dongle (elc drivers) up to date and working. As there may be required items on there.

It’s difficult to say more as you don’t provide OS or screen shot showing exactly what happened.