Im not going to be the worlds greatest help, but as far as I am aware windows links your license to you motherboard ID or something. That's why even with a license the affair is going to be messy. Because they inched claimed the license is already in use and cannot be on the new pc.
I could activate then through a Telefone Call thing. But my licence was linked to my account and it showed in my MS account on their website that I own a licence. Without that I would have had no idea to proceed.
So my first step would be to check if you have had registered your old license in your MS account.
Potentially Germany, where I grew up we said "Two idiots - one thought". We have quite a lot if regional variety in these things.
My personal experience is that I just translate one idiom from one language / culture to the other without realising and still expect ppl. to know what I mean.