How to reactivate my windows key on my formatted pc?

[Microsoft Windows]

I built my pc in 2024 and bought a windows oem key and activated windows in it. Recently I formatted the same computer and installed the windows from 0 by using a windows installment on a flash drive (Which is recently prepared). Durin the installation I entered my key, installation processes continued without any warning or any other problem. After the installation completed when I tried to switch to the dark theme on settings, I discovered my windows is not being activated. It was saying " We can't activate Windows on this device because the production key was already used on another device.

Continue reading...