You must purchase a newer version of Pinnacle Studio or use free/legal alternatives.
Originally, Pinnacle Studio 12 had an "Offline Activation" option. You would call a number or visit a website. That support line is dead. You cannot brute force this. Pinnacle Studio 12 Serial Number Activation Key
Let’s assume you have a legitimate use case. Maybe you have old project files (.stu files) that you need to render. Or you simply prefer the workflow. Here are your options. You must purchase a newer version of Pinnacle