Reenter GTA V activation code?

I had GTA V on my PC recently, but it's quite old, so I do not use it anymore. Now I have a laptop on which I have GTA V installed, but now the product code is requested again and when I enter it, then it says that I have used it before (on the old PC) I have but with the same account logged in as before… What can I do now?

I'm afraid you have to, well or ill, http://GTA%20V%20Aktivierungscode!

The previous link was somehow broken! https://www.amazon.de/...0071L2QD0/

But I can't pay now, just because I want to install the game on another device now… Above all, legally I would not have to do that…