Hi blood-king,
Sorry about your trouble. Not fun.
This sounds like a License problem, which hopefully can be fixed quickly.
Can you sign out of the app and sign in again?
It is the first screen you see when the app starts and shows you some of your work. In the left upper area is a circle with a "head" in it. This should get you going. Fingers crossed.
If that doesn't help, please check with the Tech Support:
https://www.maxon.net/en/support-center
I'm not sure if anything from that link will help you, but better to share it than not:
https://support.maxon.net/hc/en-us/sections/4408508575634-Forger
Please let me know how it goes.
Enjoy your weekend