I bought Minecraft Java edition a few years ago and I've never had any problems with it. However, lately, when I log in with my account, it says that I haven't bought the game and that I can only play the demo version. Also, every time I log in the minecraft.net website, it changes the idiom to Spanish, even though I'm Portuguese and live in Portugal.

I would like to know what can I do to be able to play Minecraft again.