"play demo" when Ive already bought the game?

Yesterday, when I went to the launcher it said "play demo" on normal minecraft and minecraft dungeons. however I downloaded and bought both of them a long time ago. I use a Microsoft account. and the weird thing? the same exact problem happened to my brother and my friends when we were trying to play together. we have had troubles where we have had to buy minecraft time after time because it wouldn't work. I'm not spending another 100$ just to play this game for a while and break down again. I do have the confirmation email.