Windows 11 Pro Activation Fails – Key Already in Use

Hello, I’m contacting you regarding an issue with product activation.

I installed Windows 11 on two PCs—one with the Home edition and the other with the Pro edition. Both licenses are genuine, fully paid, and purchased through official authorized resellers.

After installation, I realized that I needed to swap the licenses between the two PCs. I attempted to change the product keys and activate each system with the other’s license. As a result, the PC that originally had Pro successfully activated with the Home license, but the PC that originally had Home is unable to activate with the Pro license.

The system has upgraded to Pro and the additional features are available, but activation fails. The error message says that the key is already in use on another device. I even tried the “Activate by phone” option, but the automated assistant blocked the process and I couldn’t complete it.

What should I do in this situation?