I'm curious did you have an OEM license or a retail license? OEM licenses die with the mobo.

OEM licenses are for the computer, not the motherboard. The online activation historically hasn't worked if you change motherboard, but the phone line folks would always activate it for you if you explained that it was the same computer with a different motherboard.

i bought a builder license from newegg in 2017. unfortunately i was not diligent about saving the product key. this was actually the third time i had been in this scenario after changing hardware. no idea why it wouldn’t work this time around.