So, I bought Minecraft: Java Edition on the official website ([https://www.minecraft.net|https://www.minecraft.net]) with a Microsoft account. I can play Minecraft with the old launcher, but I just upgraded my launcher using the Xbox App. And when I launch this new launcher, I got the button "Play the demo" and another one "Buy the game". When I click this button, I'm in the Minecraft website. I'm connected to my Microsoft account, and it tells me that I already bought the game.