You bought a NFT on some blockchain that exists now, you didn't buy the number. I can sell that same number to someone else, and I could print a big picture of

You bought a NFT on some blockchain that exists now, you didn't buy the number. I can sell that same number to someone else, and I could print a big picture of it on fancy paper in a nice frame and afix a hologram seal of authenticity. You owning the NFT of that number doesn't give you any rights to that sale, just as my framed picture doesn't give me any rights over the NFT.