Studio 2021 suddenly deactivated and cannot be activated with the code that was valid before

Hello, 
My Studio 2021 Freelance Plus  won't start and claims it needs activation. The existing product code doesn't work.
I renamed the Studio.lic file according to Article 000001939 of RWS Support Gateway but to no avail. 
I will appreciate any hints how to solve this problem as I've been left without my tool of the trade.

Maciej Kański 

emoji